On Thu, 24 Feb 2005 16:29:05 GMT, Bruce L. Bergman
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

I have to say here that any transformer will cause more trouble than
it saves. They are OK for a sprts meeting, with long long runs, high
power and low quality, and to keep wire costs down etc. But the
impedance, oscillation, and frequency response problems of a tranny
are huge, compared to transistors and good wire of sufficient size.

If you're going more than 50'-100' or so with the signal (like "out
to the shop") use a 70-volt amplifier system to do it, and drop it
back to 8-ohm at the far end with a speaker transformer. Otherwise
you get a distorted signal trying to push 8-ohm audio too far, from
the capacitive/inductive effects of the cable. That's why they have
to apply loading coils every ~6,000' on long telephone cables.

-- Bruce --

Bob May wrote:
What is a Watt of power?

You obviously don't know. This has been beat to death hear numerous
times. Go away and learn some math.

Ted

jim rozen wrote:

Sounds to me like you really want to just put the final drivers
right *at* the voice coil inputs to the speakers. Anything
else and the impedance is going to go up.

Yeah but at 1mOhm/ft for #10 6" of leads won't do much harm. :-)

Ted

On Tue, 01 Mar 2005 04:41:15 GMT, Ted Edwards
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Ted. I am one of the beaters, as are you. The trouble is, whatever
your reasoning (and technically your ideas are correct, in many ways),
there are accepted standard ways to compare things in the industry. So
leave a bit of room for convention in the interests of communication.
You are not going to alter the system, which does work, as long as the
parameters are understood and agreed upon by those concerned.

You obviously don't know. This has been beat to death hear numerous
times. Go away and learn some math.

Ted

sd
"OldNick" wrote in message
...
On Tue, 01 Mar 2005 04:41:15 GMT, Ted Edwards
vaguely proposed a theory
......and in reply I say!:

remove ns from my header address to reply via email

Ted. I am one of the beaters, as are you. The trouble is, whatever
your reasoning (and technically your ideas are correct, in many ways),
there are accepted standard ways to compare things in the industry. So
leave a bit of room for convention in the interests of communication.

You may be explaining one of the things that I have never been able to
understand when conversing with Ted. I respect his knowledge, but have had
a hard time coming to terms with his claims, and those of others, that
rating stereo gear RMS is not a valid method, and makes no sense. Perhaps
it doesn't in the pure sense of the word, but it appears to be something the
industry does, so as long as they all play by the same rules (assuming they
do), it would be an indicator of sorts of the output capability of
electronics, at least for people like me, that have no formal electronics
education and not enough sense to understand the technical terms applied by
those that do.

This link
http://www.mcintoshlabs.com/data/rev...ighFidelity_MC
602.pdf demonstrates the fact that RMS is used as a rating method by
McIntosh, and is apparently used by at least a portion of the amplifier
industry. I can't imagine McIntosh attempting to defraud consumers, not
considering the level of quality and duration of their reputation, which has
been highly respected for years. I have to assume that there is some valid
reason for their claims and rating system, even if it goes against the
credentials of others. After all, each of the corporations as we know them
began life in a garage somewhere, likely much the same way the vast majority
of us have applied that which we love. I guess it gets down to one
person's argument over another's. RMS seems to have become established,
be it right or wrong.

Comments?

Harold





You are not going to alter the system, which does work, as long as the
parameters are understood and agreed upon by those concerned.

You obviously don't know. This has been beat to death hear numerous
times. Go away and learn some math.

Ted

On Mon, 28 Feb 2005 23:04:42 -0800, "Harold and Susan Vordos"
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Ok. None from elsewhere.

My idea about a standard is obvious. However, my comment would be that
it can be misused, because there is more to "RMS power" than face
value. See air compressor ratings and car HP. As Ted argues, it relies
on a sine wave, and IIRC also requires that the amp be able to carry
that output into the rated load for a given time.

However I still reckon that it _is_ a standard for comparison, and has
relatively simple parameters. Applied reasonably and honestly, It
allows anyone to see what the steady-state capabilities of an amp and
speakers are.

I have trouble evaluating Ted's stories of peak amps and regulated
power supplies, providing high noise levels and blowing up speakers
with 3 times the rating, because I feel that not enough info was
provided to see what was happening.

You may be explaining one of the things that I have never been able to
understand when conversing with Ted. I respect his knowledge, but have had
a hard time coming to terms with his claims, and those of others, that
rating stereo gear RMS is not a valid method, and makes no sense. Perhaps
it doesn't in the pure sense of the word, but it appears to be something the
industry does, so as long as they all play by the same rules (assuming they
do), it would be an indicator of sorts of the output capability of
electronics, at least for people like me, that have no formal electronics
education and not enough sense to understand the technical terms applied by
those that do.

This link
http://www.mcintoshlabs.com/data/rev...ighFidelity_MC
602.pdf demonstrates the fact that RMS is used as a rating method by
McIntosh, and is apparently used by at least a portion of the amplifier
Comments?

On Sun, 27 Feb 2005 22:40:29 -0800, "Harold and Susan Vordos"
wrote:



Chuckle! Not this one, Ted. The only room in the house that could be
considered remotely above a standard room is the sound room, and it's about
21' x 31'. Small house, really. I learned my lesson from building the
castle. Big houses are for people with big money. We commoners must live
accordingly.


Just a bit bigger than the footprint of my 3 bed two floor semi-detached house
;-)

Worse still, it's twice the area of my workshop :-(


Mark Rand
RTFM

"Mark Rand" wrote in message
...
On Sun, 27 Feb 2005 22:40:29 -0800, "Harold and Susan Vordos"

wrote:



Chuckle! Not this one, Ted. The only room in the house that could be
considered remotely above a standard room is the sound room, and it's
about
21' x 31'. Small house, really. I learned my lesson from building the
castle. Big houses are for people with big money. We commoners must
live
accordingly.


Just a bit bigger than the footprint of my 3 bed two floor semi-detached
house
;-)

Worse still, it's twice the area of my workshop :-(

Wow! That hurts. g

That's OK, Mark. It's not the size of the shop, but what you can get out
of it. My one car garage served me very well for 16 years.

I spent my entire self employed machining career in that one car garage.
Lots of super work, but nowhere to stand. I vowed I'd have a nice shop
when I retired. Outside dimensions, 32' X 80', with 12' ceilings. I do
have some RV storage in the building, formed by an 8" concrete block wall
that splits the building inside. There's a man door that permits inside
access. The air compressor and built in vacuum cleaner reside on that side,
so you don't have to hear them running. They are in their own room. Shop
space is now (inside) 30' 4" by about 52'. Great shop, with nothing to
do! g

Harold

On Tue, 1 Mar 2005 22:01:13 -0800, "Harold and Susan Vordos"
vaguely proposed a theory
.......and in reply I say!:

remove ns from my header address to reply via email

Ok. You spent your self-employed career in a one-car garage. And now
retired, you can get what you _want_

You won Lotto, or we admire your business acumen!

On the other hand it really sounds that the old saying "the cobbler
has ratty shoes" may well fit here! G

I am going to be a real PITA here, to myself and others. I have a 50'
* 30' * 12' shed that is sitting doing nothing, while I fill up a 20'
x 20' "shed" with my gear.

Trouble is, I have to get 350 yards of power lead to the big shed.

BAH!

Harold. Regarding the amps vs speaker wire thing. I would seriously
look at using signal lead, well-shielded and earthed and driving a new
amp, over running the power to speakers. If you have a listening room,
that's where you listen. The shed will prob. have **** acoustics, and
you are already distorting the sound if you introduce other sounds,
even if you raise the whole thing to tinnitus levels G

A halfway decent amp will be better than all the crap you are going to
do to achieve controllable music in the shop. Crickey! Use an FM
transmitter! G

You have full control over volume. You can, if you wish, enter into a
full-fledged equaliser to compensate for room acoustics, volume, etc
etc. All onsite.

No matter what LPad you use, if it will handle the power or not, your
Macintosh/speaker is being aurally abused by using it. It's simple
passive resistive stuff in a complex system that as you have read is
far from passive.

I admit that I have also started to subscribe to the "listen to the
music, not the sound" school. If you are so tied up with the system,
are you enjoying the music? I have just listened to some classical
stuff on a $50 ****-box. It definitely stole from the experience. But
even my boppy, tin-eared wife could understand the difference, so it
was extreme. _AND_ I still liked the music. With something _good_, but
not from Big Mc, the Law of Diminishing Returns bites hard. Add in
environmental shortcomings, and you multiply that.

I spent my entire self employed machining career in that one car garage.
Lots of super work, but nowhere to stand. I vowed I'd have a nice shop
when I retired. Outside dimensions, 32' X 80', with 12' ceilings. I do
have some RV storage in the building, formed by an 8" concrete block wall
that splits the building inside. There's a man door that permits inside
access. The air compressor and built in vacuum cleaner reside on that side,
so you don't have to hear them running. They are in their own room. Shop
space is now (inside) 30' 4" by about 52'. Great shop, with nothing to
do! g

s
"OldNick" wrote in message
...
snip-----

I am going to be a real PITA here, to myself and others. I have a 50'
* 30' * 12' shed that is sitting doing nothing, while I fill up a 20'
x 20' "shed" with my gear.

Trouble is, I have to get 350 yards of power lead to the big shed.

BAH!

Kids play!

We had to pay to have 3 phase power run to our location. Just over 2 miles.
Got a damned good break because the single line serving our area was in need
of upgrading anyway. We had to pay only for the third conductor, plus the
distance from the main line to our property. Worth every penny when you
consider my need, owning a 50 KW induction furnace.

Harold. Regarding the amps vs speaker wire thing. I would seriously
look at using signal lead, well-shielded and earthed and driving a new
amp, over running the power to speakers. If you have a listening room,
that's where you listen. The shed will prob. have **** acoustics, and
you are already distorting the sound if you introduce other sounds,
even if you raise the whole thing to tinnitus levels G

Yeah, I've already considered all that, but it's no different from what I'm
used to in the shop environment. My plan is just a slight modification of
something I have already done before, and I was pleased with how that one
turned out.

A halfway decent amp will be better than all the crap you are going to
do to achieve controllable music in the shop. Crickey! Use an FM
transmitter! G

You have full control over volume. You can, if you wish, enter into a
full-fledged equaliser to compensate for room acoustics, volume, etc
etc. All onsite.

I had that, minus the equalizer (had it, but not on site) with my old setup,
which I will emulate here. In fact, I have three sets of controls, the
autoformers I spoke of. They were purchased long ago, from a company in
Utah, where I used to reside, that specializes in sound distribution. I
was totally pleased with the performance they provided, and should be again.
I had the option of turning sound off completely, or louder than was
comfortable, using the same amplifier I intend to use here (barring my
buying a new one). Unless I don't understand, they don't rely on passive
resistance to function. The only difference now will be the speaker set,
which is far more capable, but still efficient. The JBL speakers have horns
for the highs and mid range--so they're not power hogs. I can't
imagine what more I'd need to be happy. I don't expect my listening while
working to parallel my listening while relaxing, just to provide music I can
tolerate. I am very selective in what I listen to and have been known to
go far out of my way to turn off that which annoys me. There will be no
Willie Nelson played here. I'm particularly hard to please when it comes to
vocalists. Can't stand the vast majority of them. I love classical
music, but not all of it. Don't even like all of jazz, my favorite. My
setup is to pacify a crotchety old man that has little patience for things
that don't please him.

No matter what LPad you use, if it will handle the power or not, your
Macintosh/speaker is being aurally abused by using it. It's simple
passive resistive stuff in a complex system that as you have read is
far from passive.

I admit that I have also started to subscribe to the "listen to the
music, not the sound" school. If you are so tied up with the system,
are you enjoying the music? I have just listened to some classical
stuff on a $50 ****-box. It definitely stole from the experience. But
even my boppy, tin-eared wife could understand the difference, so it
was extreme. _AND_ I still liked the music. With something _good_, but
not from Big Mc, the Law of Diminishing Returns bites hard. Add in
environmental shortcomings, and you multiply that.

I have been caught in the trap of listening to the system instead of the
music, but a recent experience convinces me that it's more involved than
that. I'm convinced I'd never be happy with a poor system.

Carmina Burana is a particular favorite of mine. While driving to a
distant town recently, it was being played on the radio. I drive a '94
Dodge pickup truck with a diesel engine, so it's not an old beater, it's a
reasonably new vehicle, still in excellent condition, with a reasonable
sound system. The lows were almost totally absent from the recording,
lows that I had come to love and appreciate when listening at home. From
that I learned that I'm far better off to pursue my objective in a way that
I'm familiar, and tolerate what appears to be minor imperfections in the end
result. Should my setup fail to perform adequately, I can always make
changes. Everything I've done is in conduit, so I have future options.
My approach is the least expensive of any of the options.

Assuming I live long enough to finish what appears to be an interminable
project, I'll give a report on my level of satisfaction. Don't hold your
breath!

Thanks for the comments.

Harold

Remember that these were all variations in how to measure the power output
of an amp back in the '60s. As the time went on, the method of rating the
amps got more and more fancy as the advertising guys found new ways of
measuring the voltage out of the amps and turning that into watts of power.
Some of those ratings were based upon non-real methods of measuring things.
Also note that back then, regulated power supplies were not common with the
amps so there was a difference bnetween what an amp could put out for 1
cycle or continous output. Thus, an amp that could put out 1W could
possibley put out 5W for that one cycle of output! That is a big
improvement in being able to sell the amp in a higher price class!

--
Why isn't there an Ozone Hole at the NORTH Pole?

In article ,
Harold and Susan Vordos wrote:

"OldNick" wrote in message
.. .
snip-----

[ ... ]

We had to pay to have 3 phase power run to our location. Just over 2 miles.
Got a damned good break because the single line serving our area was in need
of upgrading anyway. We had to pay only for the third conductor, plus the
distance from the main line to our property. Worth every penny when you
consider my need, owning a 50 KW induction furnace.

Beware of one problem -- assuming that you have a commercial
"demand" priced power, instead of domestic. (It is often the case that
the power company will not provide three-phase except under commercial
pricing.) That problem is that the pricing (usually for several months)
is based on the maximum load drawn within a fairly short period. So
fire up that 50 KW induction furnace, and you may find yourself paying
for power as though you were running that induction furnace full time.

Harold. Regarding the amps vs speaker wire thing. I would seriously
look at using signal lead, well-shielded and earthed and driving a new
amp, over running the power to speakers. If you have a listening room,
that's where you listen. The shed will prob. have **** acoustics, and
you are already distorting the sound if you introduce other sounds,
even if you raise the whole thing to tinnitus levels G

Yeah, I've already considered all that, but it's no different from what I'm
used to in the shop environment. My plan is just a slight modification of
something I have already done before, and I was pleased with how that one
turned out.

Is there a difference in the distance from the listening room to
the shop? (You may have spelled this out earlier in the thread, but I
came back from a couple of days away, and had so much to read that I
killed off several long threads, opting to read only what came in after
that point.)

I agree that you will get better sound from a less expensive
amplifier driving those speakers locally than from a long run with heavy
gauge wire. But -- what I would suggest that you use for the feed is
not plain shielded wire (which tends to pick up some hum over long
runs), but instead a 600 ohm balanced line driving one twisted pair
shielded per channel. The twisted pair tends to cancel out capacitive
and inductive coupling between the wires, and the balanced tends to
isolate from common mode voltage differences. Ideally, you would have
an excellent audio transformer at the input to the shop amp -- or an
input circuit which emulates that. This is the way that broadcast
audio, and recording studios route sound around without worrying about
the kind of noise pickup which normal shielded wire is vulnerable to.

Note that your Macintosh amplifier has provisions for accepting
600 ohm inputs (the three-pin connectors on the back panel, according
to the web site).

Ted's circuit may well do all that you need in the shop, and
there should be better control of the speakers with a local amp than
with one running through those long low-impedance cables which add
capacitive coupling between the conductors for one channel (which will
reduce high frequencies), and between the channels (which will cause
high frequencies intended for one channel to appear (somewhat weaker) in
the other. If your high current lines are all parallel as well, there
may also be inductive coupling.

Go ahead and run the high current wires -- but also run the
shielded twisted pair to allow a comparison test when you get a good
amplifier for the shop. They won't take up much space in the conduit.

And -- if possible, make your high current pairs twisted as well
(that is, both wires for a given channel are twisted together), which
will reduce some of the problems which they may introduce.

A halfway decent amp will be better than all the crap you are going to
do to achieve controllable music in the shop. Crickey! Use an FM
transmitter! G

You have full control over volume. You can, if you wish, enter into a
full-fledged equaliser to compensate for room acoustics, volume, etc
etc. All onsite.

I had that, minus the equalizer (had it, but not on site) with my old setup,
which I will emulate here. In fact, I have three sets of controls, the
autoformers I spoke of. They were purchased long ago, from a company in
Utah, where I used to reside, that specializes in sound distribution. I
was totally pleased with the performance they provided, and should be again.

Do they change volume in steps (that is a tapped
autotransformer), or continuously variable (like a Variac designed for
audio power levels)?

In any case, they result in variable loads applied to the
amplifier in the listening room -- with might induce some distortion
there as well.

I had the option of turning sound off completely, or louder than was
comfortable, using the same amplifier I intend to use here (barring my
buying a new one). Unless I don't understand, they don't rely on passive
resistance to function. The only difference now will be the speaker set,
which is far more capable, but still efficient. The JBL speakers have horns
for the highs and mid range--so they're not power hogs. I can't
imagine what more I'd need to be happy.

Perhaps the ability to listen in the shop without inflicting
your choices on your wife back in the main house? (I don't know how
good the acoustic isolation in your listening rom may be.)

I don't expect my listening while
working to parallel my listening while relaxing, just to provide music I can
tolerate. I am very selective in what I listen to and have been known to
go far out of my way to turn off that which annoys me. There will be no
Willie Nelson played here. I'm particularly hard to please when it comes to
vocalists. Can't stand the vast majority of them. I love classical
music, but not all of it. Don't even like all of jazz, my favorite. My
setup is to pacify a crotchety old man that has little patience for things
that don't please him.

Is your amp going to be fed from recordings, or from a tuner?
The latter would be likely to require

[ ... ]

I have been caught in the trap of listening to the system instead of the
music, but a recent experience convinces me that it's more involved than
that. I'm convinced I'd never be happy with a poor system.

Carmina Burana is a particular favorite of mine. While driving to a
distant town recently, it was being played on the radio. I drive a '94
Dodge pickup truck with a diesel engine, so it's not an old beater, it's a
reasonably new vehicle, still in excellent condition, with a reasonable
sound system. The lows were almost totally absent from the recording,
lows that I had come to love and appreciate when listening at home. From
that I learned that I'm far better off to pursue my objective in a way that
I'm familiar, and tolerate what appears to be minor imperfections in the end
result. Should my setup fail to perform adequately, I can always make
changes. Everything I've done is in conduit, so I have future options.
My approach is the least expensive of any of the options.

O.K. So try the shielded twisted pair, and Ted's amplifier. I
don't remember what he said it would cost, but if it is not too much, it
may well be worth a try.

I'm quite happy with may Hafler amp (which was a kit), and you
might be as well. I presume that they are still made.

Assuming I live long enough to finish what appears to be an interminable
project, I'll give a report on my level of satisfaction. Don't hold your
breath!

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

s
"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

"OldNick" wrote in message
.. .
snip-----

[ ... ]

We had to pay to have 3 phase power run to our location. Just over 2
iles.
Got a damned good break because the single line serving our area was in
need
of upgrading anyway. We had to pay only for the third conductor, plus
the
distance from the main line to our property. Worth every penny when you
consider my need, owning a 50 KW induction furnace.

Beware of one problem -- assuming that you have a commercial
"demand" priced power, instead of domestic. (It is often the case that
the power company will not provide three-phase except under commercial
pricing.) That problem is that the pricing (usually for several months)
is based on the maximum load drawn within a fairly short period. So
fire up that 50 KW induction furnace, and you may find yourself paying
for power as though you were running that induction furnace full time.

Yep! They (PUD, Public Utility District) installed a demand meter. I'm
so far from being able to run the induction furnace at this point I'm not
too concerned, but it's a reality for the future. One of the good things
is that I have installed twin services, with everything running through the
single phase service that can be. Shop lights, all receptacles. There are
no single phase devices of any kind that get metered through the demand
meter. I was told that the cost increase would come at 50 KW, so unless I
draw a full load, I could avoid any overcharge. I'll be careful to keep
the compressor from running when I fire up the induction furnace, and
there's nothing else I'd possibly be doing aside from running it when it's
in operation. They require almost constant attention (old technology, not
solid state) to monitor power factor, which is constantly changing as the
metal melts.

Harold. Regarding the amps vs speaker wire thing. I would seriously
look at using signal lead, well-shielded and earthed and driving a new
amp, over running the power to speakers. If you have a listening room,
that's where you listen. The shed will prob. have **** acoustics, and
you are already distorting the sound if you introduce other sounds,
even if you raise the whole thing to tinnitus levels G

Yeah, I've already considered all that, but it's no different from what
I'm
used to in the shop environment. My plan is just a slight modification
of
something I have already done before, and I was pleased with how that one
turned out.

Is there a difference in the distance from the listening room to
the shop? (You may have spelled this out earlier in the thread, but I
came back from a couple of days away, and had so much to read that I
killed off several long threads, opting to read only what came in after
that point.)

Yes, a great distance. The listening room is just over 30' deep, with the
speakers on the opposite end of the room from the electronics. I have
installed EMT conduit in which I'll run some #10 appliance cord to each of 4
speakers positions. The runs are very nearly the same length, a few feet
different from one another, necessitated by the relative location, one from
another. The shop is a different critter. From the electronics to the
shop will be in the neighborhood of 120'. Not measured, but I have a fair
idea I'm very close. Long distance is the point, not just the next room.

I agree that you will get better sound from a less expensive
amplifier driving those speakers locally than from a long run with heavy
gauge wire. But -- what I would suggest that you use for the feed is
not plain shielded wire (which tends to pick up some hum over long
runs), but instead a 600 ohm balanced line driving one twisted pair
shielded per channel. The twisted pair tends to cancel out capacitive
and inductive coupling between the wires, and the balanced tends to
isolate from common mode voltage differences. Ideally, you would have
an excellent audio transformer at the input to the shop amp -- or an
input circuit which emulates that. This is the way that broadcast
audio, and recording studios route sound around without worrying about
the kind of noise pickup which normal shielded wire is vulnerable to.

Note that your Macintosh amplifier has provisions for accepting
600 ohm inputs (the three-pin connectors on the back panel, according
to the web site).

Unfortunately, my amp is not the one you're discussing. I run an old
Mc2300, built in the mid 70's. All connections from the preamp, in and out,
and the in connections on the amp are limited to RCA jacks. Mc used them
for years with no changes. The modern gear is a product of new ownership as
far as I know.

Ted's circuit may well do all that you need in the shop, and
there should be better control of the speakers with a local amp than
with one running through those long low-impedance cables which add
capacitive coupling between the conductors for one channel (which will
reduce high frequencies), and between the channels (which will cause
high frequencies intended for one channel to appear (somewhat weaker) in
the other. If your high current lines are all parallel as well, there
may also be inductive coupling.

Chuckle! Ted's a great guy, but he didn't offer me one of his amps, which
comes as no surprise.

Go ahead and run the high current wires -- but also run the
shielded twisted pair to allow a comparison test when you get a good
amplifier for the shop. They won't take up much space in the conduit.

I have 1½" conduit in place for the run, so it shouldn't be too crowded,
regardless. I'm thinking of installing a pull piece just in case I decide
to add something in the future, at which time I could pull a second pull
piece. I realize how difficult it can be to pull wire once some occupies
the space. Possible, but often very difficult, especially on turns.

And -- if possible, make your high current pairs twisted as well
(that is, both wires for a given channel are twisted together), which
will reduce some of the problems which they may introduce.

I like that idea and will do just that. Considering I'll be running two
pairs, would you recommend I twist each pair, then twist the two pairs of
pairs? Any benefit in doing so? In either case they'll be in the same
conduit, but with the twist, perhaps there's something to gain. From all
indications, I'll have to pull through only two 90's, so the overall large
bundle should pull fairly easily---especially considering I'll be using THHN
stranded wire.

I'm going to go with my original idea, if for no other reason, it served me
well in the past, although the run was considerably shorter. Power isn't
an issue, I have more than plenty, and loss at the high end isn't a concern,
not when listening in the shop, anyway. Like most of us, my high end
isn't what it used to be. I haven't heard the sound of a flyback
transformer in a TV for a long time.


A halfway decent amp will be better than all the crap you are going to
do to achieve controllable music in the shop. Crickey! Use an FM
transmitter! G

You have full control over volume. You can, if you wish, enter into a
full-fledged equaliser to compensate for room acoustics, volume, etc
etc. All onsite.

I had that, minus the equalizer (had it, but not on site) with my old
setup,
which I will emulate here. In fact, I have three sets of controls, the
autoformers I spoke of. They were purchased long ago, from a company in
Utah, where I used to reside, that specializes in sound distribution. I
was totally pleased with the performance they provided, and should be
again.

Do they change volume in steps (that is a tapped
autotransformer), or continuously variable (like a Variac designed for
audio power levels)?

Steps. The stainless steel face plate is calibrated 0 through 10 over about
320°.


In any case, they result in variable loads applied to the
amplifier in the listening room -- with might induce some distortion
there as well.

Again, I'm not nearly as concerned with that as I would be having to listen
to a radio, where I'm subjected to music I despise. Even the jazz station
we frequent, KPLU, which is found online, plays a fair amount of music I
don't prefer. They're big on vocalists, which, for the most part, I don't
like. Of late they're playing way too much Norah Jones. She's likely a
lovely lady, but I can't stand her voice, nor her choice of songs. Mostly
related to country music. I'd rather kiss a pig on the mouth than listen to
that stuff. Ella Fitzgerald, Sarah Vaughn, Joe Williams, Mel Tormè, Nat
King Cole, Sinatra--------No problem.

Perhaps the ability to listen in the shop without inflicting
your choices on your wife back in the main house? (I don't know how
good the acoustic isolation in your listening rom may be.)


I'm a lucky guy, DoN. My wife listens to and enjoys the same music, and we
agree almost perfectly on our likes and dislikes. Neither of us like
country western, and both of us prefer the baroque when listening to
classical. She almost always is listening when I am. Both of us are real
MJQ fans, along with many others. Brubeck happens to be a favorite for both
of us. Life is good!! When I'd be in the shop, she'd likely be listening
to the other speakers in the house, as has been our habit as long as we've
been married.

Is your amp going to be fed from recordings, or from a tuner?
The latter would be likely to require

You seem to have dropped the ball here, but to answer, I'd use the system in
all ways. Tuner (we have a McIntosh MR-78 FM tuner, and don't listen to AM)
plus various playback systems, including reel to reel (Crown CX 824),
cassettes (Nakamichi 1000 II) and an inexpensive Nakamichi CD player. We
still have the turntable and our large collection of vinyl recordings, but
they don't lend themselves to shop listening because of the distance to the
listening room from the shop. Too inconvenient. We plan to add a good
quality CD player, most likely a McIntosh, when we inhabit the house. Not a
worry meantime.

I'm quite happy with may Hafler amp (which was a kit), and you
might be as well. I presume that they are still made.

Could be I would be happy with it, but I'm not sure I'd be up to the task of
assembling one. The only amplifier I ever built was when I was just a
kid, hanging out at the local radio repair store. Built it from scratch
with the help of a guy that worked there, but it would hardly qualify as an
amplifier in the scheme of things. I was crazy about electronics, but
realized early on I didn't have what it took. I was always somewhat
confused by things, very unlike machining. I made up my mind in high
school that I'd pursue machining and give up my quest to learn electronics.
When solid state devices hit the market, I was all the more confused. I
think I made a sound decision considering my aptitude for such things.


Assuming I live long enough to finish what appears to be an interminable
project, I'll give a report on my level of satisfaction. Don't hold
your
breath!

Good Luck,
DoN.

Chuckle! That I can use!

Thanks, DoN.

Harold

In article ,
Harold and Susan Vordos wrote:
s
"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

[ ... ]

Beware of one problem -- assuming that you have a commercial
"demand" priced power, instead of domestic. (It is often the case that

[ ... ]

Yep! They (PUD, Public Utility District) installed a demand meter. I'm
so far from being able to run the induction furnace at this point I'm not
too concerned, but it's a reality for the future.

Good! You know about the problem. That is the main thing.

[ ... ]

meter. I was told that the cost increase would come at 50 KW, so unless I
draw a full load, I could avoid any overcharge. I'll be careful to keep
the compressor from running when I fire up the induction furnace, and

Will the induction furnace go to full power each time, or can
you use it at reduced power?

[ ... ]

Is there a difference in the distance from the listening room to
the shop? (You may have spelled this out earlier in the thread, but I

[ ... ]

another. The shop is a different critter. From the electronics to the
shop will be in the neighborhood of 120'. Not measured, but I have a fair
idea I'm very close. Long distance is the point, not just the next room.

That makes things more difficult.

[ ... ]

Note that your Macintosh amplifier has provisions for accepting
600 ohm inputs (the three-pin connectors on the back panel, according
to the web site).

Unfortunately, my amp is not the one you're discussing. I run an old
Mc2300, built in the mid 70's. All connections from the preamp, in and out,
and the in connections on the amp are limited to RCA jacks. Mc used them
for years with no changes. The modern gear is a product of new ownership as
far as I know.

O.K. Not that it would matter, unless you got a second
Macintosh for the shop anyway. Note that you can add input transformers
to the more common RCA jacks for input and get the balanced input. And
it is a lot easier to get a big enough transformer for the power levels
involved in line level inputs (just a few db over 1 mW) than for the
speaker power levels.

Ted's circuit may well do all that you need in the shop, and
there should be better control of the speakers with a local amp than

[ ... ]

Chuckle! Ted's a great guy, but he didn't offer me one of his amps, which
comes as no surprise.

He may offer you the information to build your own, if he thinks
that you will actually *use* it.

Go ahead and run the high current wires -- but also run the
shielded twisted pair to allow a comparison test when you get a good
amplifier for the shop. They won't take up much space in the conduit.

I have 1½" conduit in place for the run, so it shouldn't be too crowded,
regardless. I'm thinking of installing a pull piece just in case I decide
to add something in the future, at which time I could pull a second pull
piece. I realize how difficult it can be to pull wire once some occupies
the space. Possible, but often very difficult, especially on turns.

Agreed. Best to pull everything at once, if possible.

I would suggest that you also run something like a 25-pair phone
cable which you could use for phones (of course), 10BaseT to connect
your shop computer to the home computer (and the outside net), *and* a
possible remote control for a CD-changer or some of the other devices.
(Obviously, the Reel-to-Reel would need to be manually rethreaded, so
that isn't much help there.)

And -- if possible, make your high current pairs twisted as well
(that is, both wires for a given channel are twisted together), which
will reduce some of the problems which they may introduce.

I like that idea and will do just that. Considering I'll be running two
pairs, would you recommend I twist each pair, then twist the two pairs of
pairs?

Nope! Just twist each pair (in the same direction -- either
both CD or both CCW -- but the same) Then run each twisted pair parallel
to the other. Twisting each pair separately minimizes crosstalk.
Twisting it all together might make things worse. And you'll need some
extra length for those twisted pairs compared to straight. How much
depends on how tight a twist. It would not hurt for one pair to be a
tighter twist than the other.

Any benefit in doing so?

No -- other than making it into a fatter bundle which will be
even more difficult to pull around corners. :-)

In either case they'll be in the same
conduit, but with the twist, perhaps there's something to gain. From all
indications, I'll have to pull through only two 90's, so the overall large
bundle should pull fairly easily---especially considering I'll be using THHN
stranded wire.

Good.

I'm going to go with my original idea, if for no other reason, it served me
well in the past, although the run was considerably shorter. Power isn't
an issue, I have more than plenty, and loss at the high end isn't a concern,
not when listening in the shop, anyway.

What I would be more concerned about with that length is
possible loss of control of speaker overtravel, thanks to the added
resistance.

Like most of us, my high end
isn't what it used to be. I haven't heard the sound of a flyback
transformer in a TV for a long time.

I was not able to hear that even when I was in high school.
Something which I and done before had damaged my high end.

[ ... ]

I had that, minus the equalizer (had it, but not on site) with my old
setup,
which I will emulate here. In fact, I have three sets of controls, the
autoformers I spoke of. They were purchased long ago, from a company in
Utah, where I used to reside, that specializes in sound distribution. I
was totally pleased with the performance they provided, and should be
again.

Do they change volume in steps (that is a tapped
autotransformer), or continuously variable (like a Variac designed for
audio power levels)?

Steps. The stainless steel face plate is calibrated 0 through 10 over about
320°.

O.K. Switched taps. That is reasonable enough for the
application -- other than changing the load impedance seen by the output
from the amplifier.

[ ... ]

Again, I'm not nearly as concerned with that as I would be having to listen
to a radio, where I'm subjected to music I despise. Even the jazz station
we frequent, KPLU, which is found online, plays a fair amount of music I
don't prefer. They're big on vocalists, which, for the most part, I don't
like. Of late they're playing way too much Norah Jones. She's likely a
lovely lady, but I can't stand her voice, nor her choice of songs. Mostly
related to country music. I'd rather kiss a pig on the mouth than listen to
that stuff. Ella Fitzgerald, Sarah Vaughn, Joe Williams, Mel Tormè, Nat
King Cole, Sinatra--------No problem.

O.K. I have my preferences for vocalists too -- in a different
field -- traditional music (what used to be called "folk music" before
the recording companies ran away with the term and changed what people
think it is.

Perhaps the ability to listen in the shop without inflicting
your choices on your wife back in the main house? (I don't know how
good the acoustic isolation in your listening rom may be.)

[ ... ]

I'm a lucky guy, DoN. My wife listens to and enjoys the same music, and we
agree almost perfectly on our likes and dislikes. Neither of us like
country western, and both of us prefer the baroque when listening to
classical. She almost always is listening when I am. Both of us are real
MJQ fans, along with many others. Brubeck happens to be a favorite for both
of us. Life is good!! When I'd be in the shop, she'd likely be listening
to the other speakers in the house, as has been our habit as long as we've
been married.

That helps. My wife won't listen to classical, though I used
to. But we are pretty much in agreement for the rest. (And we met
through the local Folklore Society. :-)

Is your amp going to be fed from recordings, or from a tuner?
The latter would be likely to require

You seem to have dropped the ball here,

Remember -- I've read only part of the thread leading up to this
point.

but to answer, I'd use the system in
all ways. Tuner (we have a McIntosh MR-78 FM tuner, and don't listen to AM)
plus various playback systems, including reel to reel (Crown CX 824),
cassettes (Nakamichi 1000 II) and an inexpensive Nakamichi CD player. We
still have the turntable and our large collection of vinyl recordings, but
they don't lend themselves to shop listening because of the distance to the
listening room from the shop.

And you certainly would not wish to subject good vinyl
recordings to the mangling from a changer.

Too inconvenient. We plan to add a good
quality CD player, most likely a McIntosh, when we inhabit the house. Not a
worry meantime.

O.K.

I'm quite happy with may Hafler amp (which was a kit), and you
might be as well. I presume that they are still made.

Could be I would be happy with it, but I'm not sure I'd be up to the task of
assembling one. The only amplifier I ever built was when I was just a
kid, hanging out at the local radio repair store. Built it from scratch
with the help of a guy that worked there, but it would hardly qualify as an
amplifier in the scheme of things. I was crazy about electronics, but
realized early on I didn't have what it took.

The Halfer kit was not that much of a kit. The wiring required
was the power supply wiring, mounting of the transformer, and connecting
input and speaker connectors to the amplifier modules which were
pre-built on heat sink modules. So it was not even as difficult as a
Heathkit (which probably had the best of assembly instructions -- the
only way to get into trouble with those was to think that you didn't
need to read some of the instructions, and forge ahead without them. :-)

They seem to have dropped the kits, anyway, and are now selling
only pre-built ones. (Hafler was the designer of the Dynaco amplifier
kits, before he started his own company.)

Here is the URL for their web site:

http://www.hafler.com/

Then go to the studio/broadcast selection, and select the P1500, which
is probably the closest to what I have (with additional features, such
as balanced input, and LED monitors.)

I was always somewhat
confused by things, very unlike machining. I made up my mind in high
school that I'd pursue machining and give up my quest to learn electronics.
When solid state devices hit the market, I was all the more confused. I
think I made a sound decision considering my aptitude for such things.

I was playing with electroncs long before I got a chance at
machine tools. The shop class in high school only taught woodworking,
which was not a good fit for me. It was not until I was working at an
Army R&D lab that I got a chance to learn machining from a couple of
resident machinists -- and I have been glad that I did. (Of course,
before that, I was trying to do things like building a tape deck for
10-1/2" reels from scratch -- mostly with hand tools and an electric
drill motor -- and files and coping saws. :-)

Again -- good luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

SNIP (hehe)


I just wanted to make a statement here... I'm somewhat of an audio man
myself... and a Sculptor to boot...

I created a pair of 54" high speakers carved from one large piece of
Basalt (harder than granite)... They won an award at the last
International VSAC (Vacuum State of the Art Convention)... yes,
that's vacuum as in Tube Amplifiers.

Anyway, as an artist... the Speakers are for sale (of course). Photos
and more information on them can be found at my web site:

www.jameskelseystudios.com

I'm 90% a metal sculptor but I do like my stone now and then....

We now continue with our regular programing.... already in
progress...

James, Seattle

"RainLover" wrote in message
news
I just wanted to make a statement here... I'm somewhat of an audio man
myself... and a Sculptor to boot...

I created a pair of 54" high speakers carved from one large piece of
Basalt (harder than granite)... They won an award at the last
International VSAC (Vacuum State of the Art Convention)... yes,
that's vacuum as in Tube Amplifiers.

Anyway, as an artist... the Speakers are for sale (of course). Photos
and more information on them can be found at my web site:

www.jameskelseystudios.com

I'm 90% a metal sculptor but I do like my stone now and then....


Do I see a little touch of David Smith? ;-)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"RainLover" wrote in message
news




SNIP (hehe)


I just wanted to make a statement here... I'm somewhat of an audio man
myself... and a Sculptor to boot...

I created a pair of 54" high speakers carved from one large piece of
Basalt (harder than granite)... They won an award at the last
International VSAC (Vacuum State of the Art Convention)... yes,
that's vacuum as in Tube Amplifiers.

Anyway, as an artist... the Speakers are for sale (of course). Photos
and more information on them can be found at my web site:

www.jameskelseystudios.com

I'm 90% a metal sculptor but I do like my stone now and then....

We now continue with our regular programing.... already in
progress...

James, Seattle

Very interesting, James. How's the sound? Can't imagine you get any strange
noises from the enclosures.

Harold

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:
snip-

What I would be more concerned about with that length is
possible loss of control of speaker overtravel, thanks to the added
resistance.

That's something I didn't understand. I guess that relates to a systems
ability to dampen. Feel free to correct me if I'm wrong.


That helps. My wife won't listen to classical, though I used
to. But we are pretty much in agreement for the rest. (And we met
through the local Folklore Society. :-)

Too bad she hasn't warmed up to the classics. That kind of listening really
has a place, at least in our lives.

It took me years to come around. I was never exposed as a young person, so
it was all very strange to me. Thanks to certain recording in the mid
60's, some jazz musicians recorded certain classical compositions. It more
or less lead me to start listening, along with a couple of acquaintances
that had very good taste in music. Didn't take me long to figure out that
the composers of the baroque era were really the jazz cats of their time.


And you certainly would not wish to subject good vinyl
recordings to the mangling from a changer.

Exactly. Regardless of how they may be perceived by others, to me they are
valuable and in some cases not available on other formats. I cherish each
and every record I have and intend to have them available for play in the
future. I'm not one of those that think they're better than a CD, not even
as good as far as I'm concerned, but if that's the only way I can have a
given performance, I'd rather have it that way than not have it. Not all
old recordings have been remastered, as you likely know.


They seem to have dropped the kits, anyway, and are now selling
only pre-built ones. (Hafler was the designer of the Dynaco amplifier
kits, before he started his own company.)

Here is the URL for their web site:

http://www.hafler.com/


Thanks for the link, which I will pursue as quickly as possible, if for no
other reason, to get a better understanding. It's highly unlikely I'd make
any decisions before finishing the house, not wanting to add anything to my
plate at this time. I'm already wasting too much time talking with everyone
on RCM, which I thoroughly enjoy. I've learned a great deal along the way,
too.


I was playing with electroncs long before I got a chance at
machine tools. The shop class in high school only taught woodworking,
which was not a good fit for me.

I share that with you. I've never enjoyed working with wood.

It was not until I was working at an
Army R&D lab that I got a chance to learn machining from a couple of
resident machinists -- and I have been glad that I did. (Of course,
before that, I was trying to do things like building a tape deck for
10-1/2" reels from scratch -- mostly with hand tools and an electric
drill motor -- and files and coping saws. :-)

After looking at the high level of precision used in building the Crown we
own, and the sophisticated controls it has, I can't even begin to understand
how a novice would go about building such a device. I really admire your
courage! I trust you were not successful, not with hand tools. g

Harold

On Wed, 2 Mar 2005 21:55:50 -0800, "Harold and Susan Vordos"
wrote:



Yep! They (PUD, Public Utility District) installed a demand meter. I'm
so far from being able to run the induction furnace at this point I'm not
too concerned, but it's a reality for the future. One of the good things
is that I have installed twin services, with everything running through the
single phase service that can be. Shop lights, all receptacles. There are
no single phase devices of any kind that get metered through the demand
meter. I was told that the cost increase would come at 50 KW, so unless I
draw a full load, I could avoid any overcharge. I'll be careful to keep
the compressor from running when I fire up the induction furnace, and
there's nothing else I'd possibly be doing aside from running it when it's
in operation. They require almost constant attention (old technology, not
solid state) to monitor power factor, which is constantly changing as the
metal melts.

Unless it's outlawed in your contract you can use a backup generator to reduce
the loading from the utility. One company I dealt with in the UK (Messrs.
Gilkes Pumps in Kendal) Were _required_ by the utility to use their backup
generator on line when running their test rig at full load.

Mark Rand
RTFM

In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:
snip-

What I would be more concerned about with that length is
possible loss of control of speaker overtravel, thanks to the added
resistance.

That's something I didn't understand. I guess that relates to a systems
ability to dampen. Feel free to correct me if I'm wrong.

You are correct. Perhaps a short explanation will help you to
understand. First off -- you want the minimum output impedance from
your amplifier, so when it wants to put out precisely 2.37 volts, it
*really* produces 2.37 volts, regardless of load (within reason -- a
short circuit can't be driven by the amp.

Now -- when you start to move the speaker cone, you do so by
applying a voltage to the voice coil. But when that coil moves in the
magnetic field, it generates a voltage of its own. If you draw current
from that, it loads down the motion of the cone, drawing energy from it.
(Like a motor overspeed will act as a generator.) The lower the
impedance of the amplifier -- and *everything* between the amplifier and
the speaker coil -- the more this motion-generated voltage will produce
a current in the opposite direction to slow down or stop the speaker.
If it is allowed to overshoot, it will introduce motion into the air
(sound) which does *not* correspond to the original recorded sound --
which we call distortion (one of many forms).

Speakers, BTW, should not be considered separate from their
enclosures. If you get a good quality speaker, and just put it cone up
on a table, and connect a 1.5V flashlight battery to it, you will hear a
"thump" sound. That means that there is a lot of low frequency
involved.

Now -- in an enclosure, the sound will be closer to a "click",
which is the true representation of the voltage step produced by the
battery. The better the speaker enclosure, and its match to the
speaker, the cleaner the "click" sound will be, and the less "thump".
(That "thump" translates into a boost in the bass curve compared to the
higher frequencies -- a "boomy" sound.)

The perfect match will produce a very clean and clear "click".
However -- if you add a resistor in series with the battery and speaker
voice coil, you will lose some of that clean click as the speaker
overshoots, comes back, undershoots, and so on until it finally stops
moving -- until you disconnect the battery.

That helps. My wife won't listen to classical, though I used
to. But we are pretty much in agreement for the rest. (And we met
through the local Folklore Society. :-)

Too bad she hasn't warmed up to the classics. That kind of listening really
has a place, at least in our lives.

Yep -- but with all else considered, I have no real complaints.
She even puts up with my shop. :-)

[ ... ]

And you certainly would not wish to subject good vinyl
recordings to the mangling from a changer.

Exactly. Regardless of how they may be perceived by others, to me they are
valuable and in some cases not available on other formats. I cherish each
and every record I have and intend to have them available for play in the
future. I'm not one of those that think they're better than a CD, not even
as good as far as I'm concerned, but if that's the only way I can have a
given performance, I'd rather have it that way than not have it. Not all
old recordings have been remastered, as you likely know.

You know -- you can get small CD recorders so you can play the
record *once* more into the recorder, and burn a CD from that, which you
can then use for many years without subjecting either the vinyl record
or the stylus (which will probably also become difficult to replace) to
more wear.

[ ... ]

Here is the URL for their web site:

http://www.hafler.com/


Thanks for the link, which I will pursue as quickly as possible, if for no
other reason, to get a better understanding. It's highly unlikely I'd make
any decisions before finishing the house, not wanting to add anything to my
plate at this time. I'm already wasting too much time talking with everyone
on RCM, which I thoroughly enjoy. I've learned a great deal along the way,
too.

I know how you feel about that. :-)


I was playing with electroncs long before I got a chance at
machine tools. The shop class in high school only taught woodworking,
which was not a good fit for me.

I share that with you. I've never enjoyed working with wood.

It does not stay put when you shape it. :-)

It was not until I was working at an
Army R&D lab that I got a chance to learn machining from a couple of
resident machinists -- and I have been glad that I did. (Of course,
before that, I was trying to do things like building a tape deck for
10-1/2" reels from scratch -- mostly with hand tools and an electric
drill motor -- and files and coping saws. :-)

After looking at the high level of precision used in building the Crown we
own, and the sophisticated controls it has, I can't even begin to understand
how a novice would go about building such a device. I really admire your
courage! I trust you were not successful, not with hand tools. g

Well ... I was successful enough so I could play tapes on it.
The motors which I used for spindle motors did not allow really good
control of fast tape motion, so I had to wait for it to run off the
supply reel. And in particular, I did not have the tools to make proper
brakes.

I was using various things which I had picked up at a surplus
vendor, including a mount for a pair of 1/4" ID ball bearings for the
spindle. I "turned" the capstan spindle with a file (after mounting
it), and used a micrometer to check my progress, until I got something
which could drive the tape at the proper speed.

I did add a saber saw to rough shape things like the pinch
roller arm, and the end-of-tape tension sensor arm, which I then
finished by filing. Those went into found bearing assemblies like that
for the capstan spindle.

I also had a "drill press" stand for the drill motor, and
quickly learned the problems with those for even an attempt at precision
work. :-)

The electronics part was easier for me, as it needed fewer
specialized tools.

Some years later, I was coming out of a hamfest (think giant
electroncs flea market), when I saw someone else walking in with a tape
deck with no elecronics. I asked him if he was taking it in to sell,
and he said "yes". So -- I bought it -- at all of $2.50 IIRC. That had
an interesting capstan motor -- it was an "inverted rotor" design -- the
rotor surrounded the coils and poles. And it was set up with three
windings, for 15 IPS, 7.5 IPS, and 3.75 IPS. I had to put new heads in
it, but everything else was as I needed it -- for several years, until
the motor burned out its windings, at which point I dove into attempting
to rewind it. I never got it quite right -- too fine a wire, I think.

That tape deck was made for military (I think Navy) use, based
on its nameplates, but was nicely built.

But -- I then picked up an Ampex 440B recorder at a surplus
sale, and later a Revox A700, so I was all set from then until I moved
to DATs for recording. *Those* I bought new. :-)

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:
snip-

What I would be more concerned about with that length is
possible loss of control of speaker overtravel, thanks to the added
resistance.

That's something I didn't understand. I guess that relates to a systems
ability to dampen. Feel free to correct me if I'm wrong.

You are correct. Perhaps a short explanation will help you to
understand. First off -- you want the minimum output impedance from
your amplifier, so when it wants to put out precisely 2.37 volts, it
*really* produces 2.37 volts, regardless of load (within reason -- a
short circuit can't be driven by the amp.

Now -- when you start to move the speaker cone, you do so by
applying a voltage to the voice coil. But when that coil moves in the
magnetic field, it generates a voltage of its own. If you draw current
from that, it loads down the motion of the cone, drawing energy from it.
(Like a motor overspeed will act as a generator.) The lower the
impedance of the amplifier -- and *everything* between the amplifier and
the speaker coil -- the more this motion-generated voltage will produce
a current in the opposite direction to slow down or stop the speaker.
If it is allowed to overshoot, it will introduce motion into the air
(sound) which does *not* correspond to the original recorded sound --
which we call distortion (one of many forms).

Speakers, BTW, should not be considered separate from their
enclosures. If you get a good quality speaker, and just put it cone up
on a table, and connect a 1.5V flashlight battery to it, you will hear a
"thump" sound. That means that there is a lot of low frequency
involved.

Now -- in an enclosure, the sound will be closer to a "click",
which is the true representation of the voltage step produced by the
battery. The better the speaker enclosure, and its match to the
speaker, the cleaner the "click" sound will be, and the less "thump".
(That "thump" translates into a boost in the bass curve compared to the
higher frequencies -- a "boomy" sound.)

The perfect match will produce a very clean and clear "click".
However -- if you add a resistor in series with the battery and speaker
voice coil, you will lose some of that clean click as the speaker
overshoots, comes back, undershoots, and so on until it finally stops
moving -- until you disconnect the battery.


Thanks for taking the time to discuss it. I was aware of the importance
of the enclosure as it relates to the speakers---and in the case of the S8R
system, JBL did something to overcome the relatively small enclosures (as
compared to the woofer, which is 15") by adding what they call a passive
radiator. A speaker without a voice coil and magnet, which, obviously,
works directly out of phase with the woofer, allowing it to have a somewhat
greater throw, therefore a slightly improved low end, at least from the
standpoint of the listener. I have no clue how it works out when subjected
to the scrutiny of instruments.

Considering we also own a Paragon, which is, for the most part, almost
identical as far as speakers go, the difference between the two is
noticeable. The Paragon doesn't have the passive radiator, but has an
exponential horn type construction, reflecting the low end off a baffle that
mounts as the base of the horn. It's clearly a better sound. I've never
been a fan of a booming low end, although I certainly do enjoy hearing a
system that has a good one. By running the Paragon and the Olympus
speakers in parallel, I get what is, to me, a very nice sound. A bit shrill
on occasion, due in part to the tweeters and mid range being horns. Of
all the speakers I listened to when I made my purchase, the only other sound
I much cared for was the wonderful, rich full sound that came from Bozak
Concert Grands, but they weren't nearly as attractive to me, and were, I
would assume, power hogs.

That helps. My wife won't listen to classical, though I used
to. But we are pretty much in agreement for the rest. (And we met
through the local Folklore Society. :-)

Too bad she hasn't warmed up to the classics. That kind of listening
really
has a place, at least in our lives.

Yep -- but with all else considered, I have no real complaints.
She even puts up with my shop. :-)

Having been through one divorce, I feel I can safely say that the value of a
good woman is difficult to determine. If your wife is anything like mine,
she just very well may be the most valuable asset you have. I have
received nothing but total cooperation from Susan in all our married life.
Right down to encouraging me to buy machines, which I rarely do.

You know -- you can get small CD recorders so you can play the
record *once* more into the recorder, and burn a CD from that, which you
can then use for many years without subjecting either the vinyl record
or the stylus (which will probably also become difficult to replace) to
more wear.


Yeah, I've given that idea considerable thought. The only thing that's
troubling is the size of the collection. With over 1,000 records, I can't
imagine ever getting them all done, but I fully intend to record at least
those that I consider my favorites. I'm sure you have certain recordings
that hold a special place in your heart. I know I do.

One of the problems with jazz is that for the most part, the grand masters
that went before us are almost all gone. While I respect the attempts of
those behind them, it's not the same. Just as in your folk music, the end
result is influenced heavily by what's happening at the moment. As
wonderful as Brubeck is today, the music he created when he was in his
younger years, performing with Desmond, will never be again. Therefore,
it's important that I retain what, to me, is what the music represents.


It was not until I was working at an
Army R&D lab that I got a chance to learn machining from a couple of
resident machinists -- and I have been glad that I did. (Of course,
before that, I was trying to do things like building a tape deck for
10-1/2" reels from scratch -- mostly with hand tools and an electric
drill motor -- and files and coping saws. :-)

After looking at the high level of precision used in building the Crown
we
own, and the sophisticated controls it has, I can't even begin to
understand
how a novice would go about building such a device. I really admire
your
courage! I trust you were not successful, not with hand tools. g

Well ... I was successful enough so I could play tapes on it.
The motors which I used for spindle motors did not allow really good
control of fast tape motion, so I had to wait for it to run off the
supply reel. And in particular, I did not have the tools to make proper
brakes.

That's certainly more success than I had imagined.


But -- I then picked up an Ampex 440B recorder at a surplus
sale, and later a Revox A700, so I was all set from then until I moved
to DATs for recording. *Those* I bought new. :-)

I bought a Teac (I think it was an A 7010) new----which was enough to
convince me that if I ever bought another deck, and I sure as hell would, it
would be a Crown. It was lacking in the quality I had hoped for.

They're (tape decks in general) really outmoded today, but I still enjoy
playing with it. I'm not in this to keep up with the Jones's, only to make
myself happy. I am.

Harold

"Mark Rand" wrote in message
...
On Wed, 2 Mar 2005 21:55:50 -0800, "Harold and Susan Vordos"

wrote:



Yep! They (PUD, Public Utility District) installed a demand meter. I'm
so far from being able to run the induction furnace at this point I'm not
too concerned, but it's a reality for the future. One of the good
things
is that I have installed twin services, with everything running through
the
single phase service that can be. Shop lights, all receptacles. There
are
no single phase devices of any kind that get metered through the demand
meter. I was told that the cost increase would come at 50 KW, so unless
I
draw a full load, I could avoid any overcharge. I'll be careful to
keep
the compressor from running when I fire up the induction furnace, and
there's nothing else I'd possibly be doing aside from running it when
it's
in operation. They require almost constant attention (old technology, not
solid state) to monitor power factor, which is constantly changing as the
metal melts.

Unless it's outlawed in your contract you can use a backup generator to
reduce
the loading from the utility. One company I dealt with in the UK (Messrs.
Gilkes Pumps in Kendal) Were _required_ by the utility to use their backup
generator on line when running their test rig at full load.

Mark Rand
RTFM


I don't know that it would be permissible, or not, but I explored the idea
of simply buying a large generator instead of paying for three phase
service. I figured I could use a small rotary phase converter for the
machines, and run only the induction furnace from the generator. When I
found that it would take something like 9 gallons/hour for fuel for a
generator that was large enough to handle the load, I abandoned the idea.
With diesel fuel now at an all time high here in our area $2.75/gallon) I
can't help but think I made a good decision.

Harold

In article ,
Harold and Susan Vordos wrote:
"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

[ ... ]

That's something I didn't understand. I guess that relates to a systems
ability to dampen. Feel free to correct me if I'm wrong.

You are correct. Perhaps a short explanation will help you to
understand. First off -- you want the minimum output impedance from

[ ... ]

Thanks for taking the time to discuss it. I was aware of the importance
of the enclosure as it relates to the speakers---and in the case of the S8R
system, JBL did something to overcome the relatively small enclosures (as
compared to the woofer, which is 15") by adding what they call a passive
radiator. A speaker without a voice coil and magnet, which, obviously,
works directly out of phase with the woofer, allowing it to have a somewhat
greater throw, therefore a slightly improved low end, at least from the
standpoint of the listener. I have no clue how it works out when subjected
to the scrutiny of instruments.

An interesting concept. Is it facing the same direction as the
powered speaker, or is it facing out the back? I see how it would allow
a greater stroke for the voice coil, and with the proper compliance, it
might actually give better sound overall.

Considering we also own a Paragon, which is, for the most part, almost
identical as far as speakers go, the difference between the two is
noticeable. The Paragon doesn't have the passive radiator, but has an
exponential horn type construction, reflecting the low end off a baffle that
mounts as the base of the horn.

Like the old Klipshorn speakers? A folded horn?

It's clearly a better sound. I've never
been a fan of a booming low end, although I certainly do enjoy hearing a
system that has a good one.

Yes -- there is a big difference between a clean bass and a
muddy, boomy one.

By running the Paragon and the Olympus
speakers in parallel, I get what is, to me, a very nice sound. A bit shrill
on occasion, due in part to the tweeters and mid range being horns. Of
all the speakers I listened to when I made my purchase, the only other sound
I much cared for was the wonderful, rich full sound that came from Bozak
Concert Grands, but they weren't nearly as attractive to me, and were, I
would assume, power hogs.

There is another interesting speaker which a friend and neighbor
has. The speakers are capacitive drivers -- big flat things just a bit
smaller than a door. Very nice sound from those, but very expensive
when new. He got both sets used at different times.

[ ... ]

Yep -- but with all else considered, I have no real complaints.
She even puts up with my shop. :-)

Having been through one divorce, I feel I can safely say that the value of a
good woman is difficult to determine. If your wife is anything like mine,
she just very well may be the most valuable asset you have. I have
received nothing but total cooperation from Susan in all our married life.
Right down to encouraging me to buy machines, which I rarely do.

And Dolores is similarly cooperative. I keep the computers
running so she can do what she wants on them, and I do the machining and
whatever in what used to be the garage. :-)

You know -- you can get small CD recorders so you can play the
record *once* more into the recorder, and burn a CD from that, which you
can then use for many years without subjecting either the vinyl record
or the stylus (which will probably also become difficult to replace) to
more wear.


Yeah, I've given that idea considerable thought. The only thing that's
troubling is the size of the collection. With over 1,000 records, I can't
imagine ever getting them all done, but I fully intend to record at least
those that I consider my favorites. I'm sure you have certain recordings
that hold a special place in your heart. I know I do.

The basic principle is to have the CD recorder connected to your
system, and whenever you pull out a record which you have not yet
treated, copy it as you play it. Sometimes you may have to do a bit of
work to set up the index and start points, other times it can be
automatic (if the inter-band gaps are the only really quiet parts).

One of the problems with jazz is that for the most part, the grand masters
that went before us are almost all gone. While I respect the attempts of
those behind them, it's not the same. Just as in your folk music, the end
result is influenced heavily by what's happening at the moment. As
wonderful as Brubeck is today, the music he created when he was in his
younger years, performing with Desmond, will never be again. Therefore,
it's important that I retain what, to me, is what the music represents.

At least there are good performers today, and there are small
recording companies who specialize in recording them -- along with
today's digital audio equipment making it easier (and less expensive) to
make a good recording at home. (Of course, it also makes it easier to
make a *terrible* recording at home. :-)

[ ... ]

After looking at the high level of precision used in building the Crown
we
own, and the sophisticated controls it has, I can't even begin to
understand
how a novice would go about building such a device. I really admire
your
courage! I trust you were not successful, not with hand tools. g

Well ... I was successful enough so I could play tapes on it.
The motors which I used for spindle motors did not allow really good
control of fast tape motion, so I had to wait for it to run off the
supply reel. And in particular, I did not have the tools to make proper
brakes.

That's certainly more success than I had imagined.

I had lots of perseverance. I wonder what I could have done
with a proper machine shop at home -- but I was in my parents home when
I started it, and I finished some later parts using a Unimat to make
them. (Things like better hub adaptors for 10-1/2" reels -- really
stretching the size capacity of the Unimat.)


But -- I then picked up an Ampex 440B recorder at a surplus
sale, and later a Revox A700, so I was all set from then until I moved
to DATs for recording. *Those* I bought new. :-)

I bought a Teac (I think it was an A 7010) new----which was enough to
convince me that if I ever bought another deck, and I sure as hell would, it
would be a Crown. It was lacking in the quality I had hoped for.

The Ampex AG440B was what was used in recording studios before
the multi-track became the way to work, and was a later model of what
had first triggered my interest. The Revox A700 was made by
Studer-Revox, who also made professional studio recorders. It was the
most gentle machine on tape handling of any that I have ever used. It
had a tension arm on each side, which controlled the tension in the
takeup and feed reel spindles to adjust for the fact that a nearly empty
reel would otherwise pull harder than a nearly full reel.

They're (tape decks in general) really outmoded today, but I still enjoy
playing with it. I'm not in this to keep up with the Jones's, only to make
myself happy. I am.

I understand, and feel the same. I do have some more modern
recording equipment -- a nice DAT recorder, and a small mix board which
I have used for recording live performances at various places, including
at the Mystic Seaport museum's annual sea music festival -- until the
last two years, when we have not been able to get there for various
reasons.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:
"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

[ ... ]

That's something I didn't understand. I guess that relates to a
systems
ability to dampen. Feel free to correct me if I'm wrong.

You are correct. Perhaps a short explanation will help you to
understand. First off -- you want the minimum output impedance from

[ ... ]

Thanks for taking the time to discuss it. I was aware of the
importance
of the enclosure as it relates to the speakers---and in the case of the
S8R
system, JBL did something to overcome the relatively small enclosures (as
compared to the woofer, which is 15") by adding what they call a passive
radiator. A speaker without a voice coil and magnet, which, obviously,
works directly out of phase with the woofer, allowing it to have a
somewhat
greater throw, therefore a slightly improved low end, at least from the
standpoint of the listener. I have no clue how it works out when
subjected
to the scrutiny of instruments.

An interesting concept. Is it facing the same direction as the
powered speaker, or is it facing out the back? I see how it would allow
a greater stroke for the voice coil, and with the proper compliance, it
might actually give better sound overall.

They're mounted side by side on the front panel, which is, in turn, covered
with a wooden grill with a cloth backing. Instinctively you're inclined to
think that setup would cancel sound, but it doesn't appear to do so. I
can't help but wonder if the ever so slight time delay (compression and
decompression) doesn't just widen the bass somewhat, providing a slightly
sustained sound. Dunno.

If you like Danish modern furniture ( and I do) both the Paragon and the
Olympus speakers are quite attractive, at least to me. I started my quest
to own them back in the late 50's. I wont dispute the fact that the design
was very much a part of the reason I wanted them, but I've always liked the
sound, too. The 375 driver for the mid range is likely the toughest driver
ever produced, and is still being manufactured for commercial use. that's
not exactly a bad thing, considering the design is about 50 years old now.
I don't have a clue how it stacks up according to the "experts", but it has
a super good track record. Used ones were selling for a small fortune a
year ago on ebay. Haven't checked since then, so I don't know it they're
still in demand.

Mid range is in the center, with the tweeters mounted on the appropriate
top end, right for right, left for left. It's interesting to watch the
woofer work with heavy passages. It's obvious the difference the passive
radiator makes by the throw one sees. The low end of the JBL speakers I'm
familiar with are not muddy in the least, so I feel it was a grand
improvement.


Considering we also own a Paragon, which is, for the most part, almost
identical as far as speakers go, the difference between the two is
noticeable. The Paragon doesn't have the passive radiator, but has an
exponential horn type construction, reflecting the low end off a baffle
that
mounts as the base of the horn.

Like the old Klipshorn speakers? A folded horn?

Not really knowing exactly what that might be, envision the woofers mounted
nearly at the center of the overall cabinet. The Paragon is made in three
pieces, left side, right side, and front panel, which provide stereo
separation regardless of your position in the room. The woofers mount on
a board that faces the center end, at a slight angle, perhaps 6 inches away
from the end. The sound is redirected from the end of the enclosure and
begins what appears to be an exponential horn design, getting wider and
wider as it approaches the end, some 42" distant. I'm not sure I'm
describing as well as it could be described.



There is another interesting speaker which a friend and neighbor
has. The speakers are capacitive drivers -- big flat things just a bit
smaller than a door. Very nice sound from those, but very expensive
when new. He got both sets used at different times.

I wonder---would that be a planer type speaker? I recall a casual
acquaintance bought a set like that some time ago. I heard them only once,
but he had trouble driving them, lacking enough power to do a good job. I
seem to recall he was using a Carter amp, but that's about all I can
remember.

[ ... ]

Yep -- but with all else considered, I have no real complaints.
She even puts up with my shop. :-)

Having been through one divorce, I feel I can safely say that the value
of a
good woman is difficult to determine. If your wife is anything like
mine,
she just very well may be the most valuable asset you have. I have
received nothing but total cooperation from Susan in all our married
life.
Right down to encouraging me to buy machines, which I rarely do.

And Dolores is similarly cooperative. I keep the computers
running so she can do what she wants on them, and I do the machining and
whatever in what used to be the garage. :-)

Very, very cool, DoN!

You know -- you can get small CD recorders so you can play the
record *once* more into the recorder, and burn a CD from that, which
you
can then use for many years without subjecting either the vinyl record
or the stylus (which will probably also become difficult to replace) to
more wear.


Yeah, I've given that idea considerable thought. The only thing that's
troubling is the size of the collection. With over 1,000 records, I can't
imagine ever getting them all done, but I fully intend to record at least
those that I consider my favorites. I'm sure you have certain
recordings
that hold a special place in your heart. I know I do.

The basic principle is to have the CD recorder connected to your
system, and whenever you pull out a record which you have not yet
treated, copy it as you play it. Sometimes you may have to do a bit of
work to set up the index and start points, other times it can be
automatic (if the inter-band gaps are the only really quiet parts).

Maybe I didn't fully understand your comment. I was under the impression
you did this with the use of a computer, which an elderly friend has been
doing for some time now. Not so?

One of the problems with jazz is that for the most part, the grand
masters
that went before us are almost all gone. While I respect the attempts
of
those behind them, it's not the same. Just as in your folk music, the
end
result is influenced heavily by what's happening at the moment. As
wonderful as Brubeck is today, the music he created when he was in his
younger years, performing with Desmond, will never be again.
Therefore,
it's important that I retain what, to me, is what the music represents.

At least there are good performers today, and there are small
recording companies who specialize in recording them -- along with
today's digital audio equipment making it easier (and less expensive) to
make a good recording at home. (Of course, it also makes it easier to
make a *terrible* recording at home. :-)

Chuckle! Hard to argue with that!

[ ... ]

After looking at the high level of precision used in building the
Crown
we
own, and the sophisticated controls it has, I can't even begin to
understand
how a novice would go about building such a device. I really admire
your
courage! I trust you were not successful, not with hand tools. g

Well ... I was successful enough so I could play tapes on it.
The motors which I used for spindle motors did not allow really good
control of fast tape motion, so I had to wait for it to run off the
supply reel. And in particular, I did not have the tools to make
proper
brakes.

That's certainly more success than I had imagined.

I had lots of perseverance. I wonder what I could have done
with a proper machine shop at home -- but I was in my parents home when
I started it, and I finished some later parts using a Unimat to make
them. (Things like better hub adaptors for 10-1/2" reels -- really
stretching the size capacity of the Unimat.)

I ran a large order of those for Univac years ago, but for computers, not
tape recorders. It was a demanding job using my Bridgeport and Graziano.
I still have one of them. My hat's off to you, DoN.

The Ampex AG440B was what was used in recording studios before
the multi-track became the way to work, and was a later model of what
had first triggered my interest. The Revox A700 was made by
Studer-Revox, who also made professional studio recorders. It was the
most gentle machine on tape handling of any that I have ever used. It
had a tension arm on each side, which controlled the tension in the
takeup and feed reel spindles to adjust for the fact that a nearly empty
reel would otherwise pull harder than a nearly full reel.

I wonder. Does the Studer name come connected to precision machine tools?
Studer is (was?) a builder of precision grinders. It would make sense that
they were somehow connected when you consider the high precision related to
the feed mechanisms of tape decks.

They're (tape decks in general) really outmoded today, but I still enjoy
playing with it. I'm not in this to keep up with the Jones's, only to
make
myself happy. I am.

I understand, and feel the same. I do have some more modern
recording equipment -- a nice DAT recorder, and a small mix board which
I have used for recording live performances at various places, including
at the Mystic Seaport museum's annual sea music festival -- until the
last two years, when we have not been able to get there for various
reasons.

Ever attend the Newport Jazz Festival? It's not what it used to be,
primarily because things change, but it used to be killer good for my taste.
I think Brubeck is about the only one left that still attends, but not
always. Many of the new guys play a sound I'm not nuts about, but at least
they're carrying on the tradition.

Harold

On Fri, 4 Mar 2005 01:40:44 -0800, "Harold and Susan Vordos"
wrote:


"RainLover" wrote in message
news




SNIP (hehe)


I just wanted to make a statement here... I'm somewhat of an audio man
myself... and a Sculptor to boot...

I created a pair of 54" high speakers carved from one large piece of
Basalt (harder than granite)... They won an award at the last
International VSAC (Vacuum State of the Art Convention)... yes,
that's vacuum as in Tube Amplifiers.

Anyway, as an artist... the Speakers are for sale (of course). Photos
and more information on them can be found at my web site:

www.jameskelseystudios.com

I'm 90% a metal sculptor but I do like my stone now and then....

We now continue with our regular programing.... already in
progress...

James, Seattle

Very interesting, James. How's the sound? Can't imagine you get any strange
noises from the enclosures.

Harold


They sound incredibly crisp and live. At VSAC, I had a couple of
African CDs.. Lot's of acappella and drums... as well as a wide
variety of vocalizing. They blew away the competion.

It was fun, most people didn't know they were mine, so I was able to
sit in the room and listen to comments.... I never get that sort of
feedback alone in my studio.

The stone itself is thick enough as to not allow the sound vibrations
to travel from the drivers to the enclosures, and inside, because I
used a 2" core drill to hollow them out, there's no smooth surface for
any sort of reverberation or echo.

They sounded incredible... although, the flee amps (under 1 or 2
watts) couldn't power them since the drivers took a bit more, but with
a robust 5 watt amplifier, they sang out.

It's too bad I don't have the high-end audio equipment at my home in
order to do them justice.... so here, they just sit as sculpture.

James, Seattle

"RainLover" wrote in message
...
On Fri, 4 Mar 2005 01:40:44 -0800, "Harold and Susan Vordos"
wrote:


"RainLover" wrote in message
news




SNIP (hehe)


I just wanted to make a statement here... I'm somewhat of an audio man
myself... and a Sculptor to boot...

I created a pair of 54" high speakers carved from one large piece of
Basalt (harder than granite)... They won an award at the last
International VSAC (Vacuum State of the Art Convention)... yes,
that's vacuum as in Tube Amplifiers.

Anyway, as an artist... the Speakers are for sale (of course). Photos
and more information on them can be found at my web site:

www.jameskelseystudios.com

I'm 90% a metal sculptor but I do like my stone now and then....

We now continue with our regular programing.... already in
progress...

James, Seattle

Very interesting, James. How's the sound? Can't imagine you get any
strange
noises from the enclosures.

Harold


They sound incredibly crisp and live. At VSAC, I had a couple of
African CDs.. Lot's of acappella and drums... as well as a wide
variety of vocalizing. They blew away the competion.

It was fun, most people didn't know they were mine, so I was able to
sit in the room and listen to comments.... I never get that sort of
feedback alone in my studio.

The stone itself is thick enough as to not allow the sound vibrations
to travel from the drivers to the enclosures, and inside, because I
used a 2" core drill to hollow them out, there's no smooth surface for
any sort of reverberation or echo.

They sounded incredible... although, the flee amps (under 1 or 2
watts) couldn't power them since the drivers took a bit more, but with
a robust 5 watt amplifier, they sang out.

That I can easily believe. When I'm listening to music, not the system (it's
different) I'm astonished at how little wattage it takes to fill a room for
comfortable listening.. Our McIntosh amp has meters that are reputed to
track wattage precisely---The meters are equipped with switches to select
ranges, so a few watts can be a full scale on the meters.

It's too bad I don't have the high-end audio equipment at my home in
order to do them justice.... so here, they just sit as sculpture.

Agreed! I can only imagine how well they might respond to some serious
power.

Way cool, James.

Harold

In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...

[ ... passive radiator ... ]

An interesting concept. Is it facing the same direction as the
powered speaker, or is it facing out the back? I see how it would allow
a greater stroke for the voice coil, and with the proper compliance, it
might actually give better sound overall.

They're mounted side by side on the front panel, which is, in turn, covered
with a wooden grill with a cloth backing. Instinctively you're inclined to
think that setup would cancel sound, but it doesn't appear to do so. I
can't help but wonder if the ever so slight time delay (compression and
decompression) doesn't just widen the bass somewhat, providing a slightly
sustained sound. Dunno.

Hmm ... is there perhaps some kind of baffle to delay the sound
from the driven speaker to the passive one? But that would likely make
it peak at certain frequencies and cancel at others. (But maybe this
would happen at frequencies that those speaker elements were not fed,
being more the job of the midrange and tweeters.)

If you like Danish modern furniture ( and I do) both the Paragon and the
Olympus speakers are quite attractive, at least to me. I started my quest
to own them back in the late 50's. I wont dispute the fact that the design
was very much a part of the reason I wanted them, but I've always liked the
sound, too. The 375 driver for the mid range is likely the toughest driver
ever produced, and is still being manufactured for commercial use. that's
not exactly a bad thing, considering the design is about 50 years old now.

A *good* design does not need changing. (Though it is likely to
suffer it if the bean counters get a hand in production.)

I don't have a clue how it stacks up according to the "experts", but it has
a super good track record. Used ones were selling for a small fortune a
year ago on ebay. Haven't checked since then, so I don't know it they're
still in demand.

They probably are.

Mid range is in the center, with the tweeters mounted on the appropriate
top end, right for right, left for left. It's interesting to watch the
woofer work with heavy passages. It's obvious the difference the passive
radiator makes by the throw one sees. The low end of the JBL speakers I'm
familiar with are not muddy in the least, so I feel it was a grand
improvement.

Great! I presume that there is no grill cloth mounted in front
of those elements.

Considering we also own a Paragon, which is, for the most part, almost
identical as far as speakers go, the difference between the two is
noticeable. The Paragon doesn't have the passive radiator, but has an
exponential horn type construction, reflecting the low end off a baffle
that
mounts as the base of the horn.

Like the old Klipshorn speakers? A folded horn?

Not really knowing exactly what that might be, envision the woofers mounted
nearly at the center of the overall cabinet. The Paragon is made in three
pieces, left side, right side, and front panel, which provide stereo
separation regardless of your position in the room. The woofers mount on
a board that faces the center end, at a slight angle, perhaps 6 inches away
from the end. The sound is redirected from the end of the enclosure and
begins what appears to be an exponential horn design, getting wider and
wider as it approaches the end, some 42" distant. I'm not sure I'm
describing as well as it could be described.

Well ... I'm going to try to describe a Klipshorn from memory,
and there is a good chance that I will be mis-remembering. If anyone
else is still following this thread, they may toss in a correction.

Anyway -- the speaker cabinet was designed to sit in the corner
of the room, using the walls on both sides as an extension of the horn.

The speaker was mounted at the top, directed downwards, and the
front opening started quite narrow at the top and widened in a clean
curve towards the bottom. The back of the cabinet was sloped towards
the front at the bottom, to redirect the sound out towards the listener.

They did not sound like much standing in the middle of a room,
but properly mounted in the corners, with clean walls on each side, they
really came to life.

There is another interesting speaker which a friend and neighbor
has. The speakers are capacitive drivers -- big flat things just a bit
smaller than a door. Very nice sound from those, but very expensive
when new. He got both sets used at different times.

I wonder---would that be a planer type speaker?

Yes.

I recall a casual
acquaintance bought a set like that some time ago. I heard them only once,
but he had trouble driving them, lacking enough power to do a good job. I
seem to recall he was using a Carter amp,

"Carter" or "Carver"? IIRC, the Carver does some strange
processing to try to "improve" the sound. While my Halfer is plain and
straightforward -- pretty much DC from just past the input coupling
capacitor to the speakers. That coupling capacitor was to keep DC from
whatever preamp you used from biasing the speaker cones away from the
central at-rest position.

but that's about all I can
remember.

I have yet to hear anything being played on his speakers -- he
and I are working with computers too much when I am there.

[ ... good wives ... ]

Right down to encouraging me to buy machines, which I rarely do.

And Dolores is similarly cooperative. I keep the computers
running so she can do what she wants on them, and I do the machining and
whatever in what used to be the garage. :-)

Very, very cool, DoN!

She even searches eBay for tools for me -- and has not yet
learned to not say "this one sounds strange" and attract my attention. :-)

[ ... burning CDs of your (irreplaceable) vinyl recordings ... ]

The basic principle is to have the CD recorder connected to your
system, and whenever you pull out a record which you have not yet
treated, copy it as you play it. Sometimes you may have to do a bit of
work to set up the index and start points, other times it can be
automatic (if the inter-band gaps are the only really quiet parts).

Maybe I didn't fully understand your comment. I was under the impression
you did this with the use of a computer, which an elderly friend has been
doing for some time now. Not so?

Not so -- though that is one way to do it. There are small
boxes available which can be connected to your system (typically the
"recorder" output from the preamp, so your adjusting of the volume for
listening won't affect the recording level -- even if you have to turn
the volume all the way down to answer a phone call). It sits there and
captures the audio. You then may wish to interact with the box a
little, to set index points so you can skip to a given cut -- that may
do well on automatic, or you may wish to adjust it. Certainly the
automatic indexing does not work well in a live concert with the
performer talking and introducing the song and telling where it is from.

[ ... home built tape player deck ... ]

That's certainly more success than I had imagined.

I had lots of perseverance. I wonder what I could have done
with a proper machine shop at home -- but I was in my parents home when
I started it, and I finished some later parts using a Unimat to make
them. (Things like better hub adaptors for 10-1/2" reels -- really
stretching the size capacity of the Unimat.)

I ran a large order of those for Univac years ago, but for computers, not
tape recorders. It was a demanding job using my Bridgeport and Graziano.
I still have one of them. My hat's off to you, DoN.

Those are a lot more complex than what I was making. Start with
a cylinder of aluminum just a little thinner than the thickness of the
tape reel. Mount to it a flange of aluminum turned to give a lip which
will hold down the reel by a radial distance of about 1/8" greater than
the through hole. Drill three holes at 120 degree intervals, and put in
pins with the ends turned to fit the three notches in the reel, and pin
them in. Then make a collet style gripper to hold onto the bare
spindle.

Nothing like the computer tape hubs, with a D-handle to expand
and grip the (rather heavier) reel with no notches for the drive pins.

The Ampex AG440B was what was used in recording studios before
the multi-track became the way to work, and was a later model of what
had first triggered my interest. The Revox A700 was made by
Studer-Revox, who also made professional studio recorders. It was the
most gentle machine on tape handling of any that I have ever used. It
had a tension arm on each side, which controlled the tension in the
takeup and feed reel spindles to adjust for the fact that a nearly empty
reel would otherwise pull harder than a nearly full reel.

I wonder. Does the Studer name come connected to precision machine tools?

It may well be. The machining of the drive is beautifully done.

Studer is (was?) a builder of precision grinders. It would make sense that
they were somehow connected when you consider the high precision related to
the feed mechanisms of tape decks.

Especially in these ones. IIRC, the Studer in question is
Swiss.

[ ... ]

I understand, and feel the same. I do have some more modern
recording equipment -- a nice DAT recorder, and a small mix board which
I have used for recording live performances at various places, including
at the Mystic Seaport museum's annual sea music festival -- until the
last two years, when we have not been able to get there for various
reasons.

Ever attend the Newport Jazz Festival? It's not what it used to be,
primarily because things change, but it used to be killer good for my taste.
I think Brubeck is about the only one left that still attends, but not
always. Many of the new guys play a sound I'm not nuts about, but at least
they're carrying on the tradition.

No -- I have not attended it -- though I have heard recordings
from it. (And also -- some from the Newport Folk Festival, which was
shut down before I got to where I could possibly attend.)

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...

[ ... passive radiator ... ]

An interesting concept. Is it facing the same direction as the
powered speaker, or is it facing out the back? I see how it would
allow
a greater stroke for the voice coil, and with the proper compliance, it
might actually give better sound overall.

They're mounted side by side on the front panel, which is, in turn,
covered
with a wooden grill with a cloth backing. Instinctively you're inclined
to
think that setup would cancel sound, but it doesn't appear to do so. I
can't help but wonder if the ever so slight time delay (compression and
decompression) doesn't just widen the bass somewhat, providing a slightly
sustained sound. Dunno.

Hmm ... is there perhaps some kind of baffle to delay the sound
from the driven speaker to the passive one? But that would likely make
it peak at certain frequencies and cancel at others. (But maybe this
would happen at frequencies that those speaker elements were not fed,
being more the job of the midrange and tweeters.)

No---no baffles of any kind. I've had the woofers out of all of the
speakers to be reconed. They have a foam rim that eventually deteriorates
and must be replaced. Heavy passages can actually tear them apart
completely, although mine have never gone that far.

My first set was purchased way back in '67, new, from a JBL dealership.
It was 9 years later when I noticed the failure of the foam. Believe it or
not, JBL reconed the speakers free of charge, thanks to their then life-time
material and workmanship warranty. They even paid for the return shipping,
California to Utah. Needless to say, that all went away when the high
end home speakers were abandoned. I'm not convinced JBL sells anything
today that's noteworthy.



Mid range is in the center, with the tweeters mounted on the appropriate
top end, right for right, left for left. It's interesting to watch the
woofer work with heavy passages. It's obvious the difference the
passive
radiator makes by the throw one sees. The low end of the JBL speakers
I'm
familiar with are not muddy in the least, so I feel it was a grand
improvement.

Great! I presume that there is no grill cloth mounted in front
of those elements.

There is a very light weight black cloth that is stretched tight and stapled
appropriately. Doesn't seem to create any strange noises, and performs a
fairly important function of masking what's behind the wooden grills. I
think they spent enough time with the design to insure it was a good one,
but I have no way of knowing if it is, or not.


Well ... I'm going to try to describe a Klipshorn from memory,
and there is a good chance that I will be mis-remembering. If anyone
else is still following this thread, they may toss in a correction.

Anyway -- the speaker cabinet was designed to sit in the corner
of the room, using the walls on both sides as an extension of the horn.

The speaker was mounted at the top, directed downwards, and the
front opening started quite narrow at the top and widened in a clean
curve towards the bottom. The back of the cabinet was sloped towards
the front at the bottom, to redirect the sound out towards the listener.

They did not sound like much standing in the middle of a room,
but properly mounted in the corners, with clean walls on each side, they
really came to life.

I recall the speakers, but didn't investigate them at all because of my
partiality to JBL. Your description tells me everything I needed to know,
however. Bose has used that same principle for years, permitting low end
speakers to perform at a much higher level that they otherwise would be
capable. I've run my S8R speakers backwards in a room and the difference
is staggering. They develop a huge low end, still clean, but with my high
end hearing slowly deteriorating, I noticed I was missing some of the highs.
One cut in particular, a Jacques Loussier recording, I often completely lost
the sound on a soft drum solo where there was considerable cymbal work.
Susan could hear it, however. The speakers were used in that fashion by
need, stacked one on top of the other in a small room.

There is another interesting speaker which a friend and neighbor
has. The speakers are capacitive drivers -- big flat things just a bit
smaller than a door. Very nice sound from those, but very expensive
when new. He got both sets used at different times.

I wonder---would that be a planer type speaker?

Yes.

I think that should be a plan*a*r speaker, but I appreciate that you
understood my comment.

I recall a casual
acquaintance bought a set like that some time ago. I heard them only
once,
but he had trouble driving them, lacking enough power to do a good job.
I
seem to recall he was using a Carter amp,

"Carter" or "Carver"? IIRC, the Carver does some strange
processing to try to "improve" the sound. While my Halfer is plain and
straightforward -- pretty much DC from just past the input coupling
capacitor to the speakers. That coupling capacitor was to keep DC from
whatever preamp you used from biasing the speaker cones away from the
central at-rest position.

Blush! Yep, I think it was Carver. I recall that he was interested in
Mc gear, but couldn't come to terms with the cost. He often offered to
store mine for me while we were building the castle. g


And Dolores is similarly cooperative. I keep the computers
running so she can do what she wants on them, and I do the machining
and
whatever in what used to be the garage. :-)

Very, very cool, DoN!

She even searches eBay for tools for me -- and has not yet
learned to not say "this one sounds strange" and attract my attention. :-)

How cool is that? Susan has no clue about tools, but she sure encourages
me.

[ ... burning CDs of your (irreplaceable) vinyl recordings ... ]

The basic principle is to have the CD recorder connected to your
system, and whenever you pull out a record which you have not yet
treated, copy it as you play it. Sometimes you may have to do a bit of
work to set up the index and start points, other times it can be
automatic (if the inter-band gaps are the only really quiet parts).

Maybe I didn't fully understand your comment. I was under the
impression
you did this with the use of a computer, which an elderly friend has been
doing for some time now. Not so?

Not so -- though that is one way to do it. There are small
boxes available which can be connected to your system (typically the
"recorder" output from the preamp, so your adjusting of the volume for
listening won't affect the recording level -- even if you have to turn
the volume all the way down to answer a phone call). It sits there and
captures the audio. You then may wish to interact with the box a
little, to set index points so you can skip to a given cut -- that may
do well on automatic, or you may wish to adjust it. Certainly the
automatic indexing does not work well in a live concert with the
performer talking and introducing the song and telling where it is from.

Thanks for the information. My limited exposure to anything electronics is
really taking a toll on me. The nearest hi fi shop is at least 100 miles
away, so I'll have to do some serious inquiring when it comes time to make
decisions. It's nice to know there's people out there that keep informed.
I'll likely call on you for advice when I get near, DoN.


I wonder. Does the Studer name come connected to precision machine
tools?

It may well be. The machining of the drive is beautifully done.

Studer is (was?) a builder of precision grinders. It would make sense
that
they were somehow connected when you consider the high precision related
to
the feed mechanisms of tape decks.

Especially in these ones. IIRC, the Studer in question is
Swiss.

As are the grinders as far as I know. I've not operated one, but have seen
one. They are reputed to be able to work to .000010" (according to the
shop people at Litton Guidance, where I saw the machine in use), a far
smaller figure than the B&S # 1 universal machines I used to operate. We
routinely held .000050", but anything closer was pretty much hit and miss.
I gathered from the comments at Litton that they were a superb machine.

Harold

In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...

[ ... ]

[ ... passive radiator ... ]

[ ... ]

Hmm ... is there perhaps some kind of baffle to delay the sound
from the driven speaker to the passive one? But that would likely make
it peak at certain frequencies and cancel at others. (But maybe this
would happen at frequencies that those speaker elements were not fed,
being more the job of the midrange and tweeters.)

No---no baffles of any kind. I've had the woofers out of all of the
speakers to be reconed. They have a foam rim that eventually deteriorates
and must be replaced. Heavy passages can actually tear them apart
completely, although mine have never gone that far.

I've seen that happen. A problem with pretty much *any* foam
rubber over time, and a foam rim does give significantly better
compliance than the tar-soaked paper or cloth ones with multiple pleats.

[ ... ]

California to Utah. Needless to say, that all went away when the high
end home speakers were abandoned. I'm not convinced JBL sells anything
today that's noteworthy.

I strongly suspect that you are correct in that.

Mid range is in the center, with the tweeters mounted on the appropriate
top end, right for right, left for left. It's interesting to watch the
woofer work with heavy passages. It's obvious the difference the
passive
radiator makes by the throw one sees.

[ ... ]

Great! I presume that there is no grill cloth mounted in front
of those elements.

There is a very light weight black cloth that is stretched tight and stapled
appropriately. Doesn't seem to create any strange noises, and performs a
fairly important function of masking what's behind the wooden grills. I
think they spent enough time with the design to insure it was a good one,
but I have no way of knowing if it is, or not.

O.K. My comment was because of your mention of watching the
woofer work with heavy passages.

[ ... ]

but with my high
end hearing slowly deteriorating, I noticed I was missing some of the highs.

My high end has been terrible since at least mid high-school,
when my hearing was first tested.

One cut in particular, a Jacques Loussier recording, I often completely lost
the sound on a soft drum solo where there was considerable cymbal work.

I pretty much don't hear much of that.

Susan could hear it, however. The speakers were used in that fashion by
need, stacked one on top of the other in a small room.

I understand the problems with a small room.

There is another interesting speaker which a friend and neighbor
has. The speakers are capacitive drivers -- big flat things just a bit
smaller than a door. Very nice sound from those, but very expensive
when new. He got both sets used at different times.

I wonder---would that be a planer type speaker?

Yes.

I think that should be a plan*a*r speaker, but I appreciate that you
understood my comment.

I didn't pay any attention to the spelling -- I did know what
you meant.

[ ... ]

seem to recall he was using a Carter amp,

"Carter" or "Carver"? IIRC, the Carver does some strange
processing to try to "improve" the sound. While my Halfer is plain and
straightforward -- pretty much DC from just past the input coupling
capacitor to the speakers. That coupling capacitor was to keep DC from
whatever preamp you used from biasing the speaker cones away from the
central at-rest position.

Blush! Yep, I think it was Carver. I recall that he was interested in
Mc gear, but couldn't come to terms with the cost. He often offered to
store mine for me while we were building the castle. g

The Carver design seemed to me to be too much "snake oil", while
the Hafler design was plain and straightforward, trading a little extra
power dissipation (running in Class-A push-pull to eliminate crossover
distortion) to get the better sound quality.

[ ... ]

She even searches eBay for tools for me -- and has not yet
learned to not say "this one sounds strange" and attract my attention. :-)

How cool is that? Susan has no clue about tools, but she sure encourages
me.

Dolores has no idea how to *use* them -- but she is good at
recognizing them. She finally found a cut-style knurler which did not
go sky high (compared to new price), and which fits my tool holders, so
I can start to experience that capability. (Well ... I do already have
one in the form of a long-armed 3-jaw chuck which works on the turret,
but that has a limited travel.

[ ... burning CDs of your (irreplaceable) vinyl recordings ... ]

Not so -- though that is one way to do it. There are small
boxes available which can be connected to your system (typically the
"recorder" output from the preamp, so your adjusting of the volume for
listening won't affect the recording level -- even if you have to turn
the volume all the way down to answer a phone call). It sits there and
captures the audio. You then may wish to interact with the box a
little, to set index points so you can skip to a given cut -- that may
do well on automatic, or you may wish to adjust it. Certainly the
automatic indexing does not work well in a live concert with the
performer talking and introducing the song and telling where it is from.

Thanks for the information. My limited exposure to anything electronics is
really taking a toll on me. The nearest hi fi shop is at least 100 miles
away, so I'll have to do some serious inquiring when it comes time to make
decisions. It's nice to know there's people out there that keep informed.
I'll likely call on you for advice when I get near, DoN.

O.K. By then I might have actually gotten around to picking up
one for my own use. I'm not sure how easy they are to find. I'll be
getting mine through a local professional audio vendor.

[ ... ]

I wonder. Does the Studer name come connected to precision machine
tools?

It may well be. The machining of the drive is beautifully done.

[ ... ]

Especially in these ones. IIRC, the Studer in question is
Swiss.

As are the grinders as far as I know. I've not operated one, but have seen
one. They are reputed to be able to work to .000010" (according to the
shop people at Litton Guidance, where I saw the machine in use), a far
smaller figure than the B&S # 1 universal machines I used to operate. We
routinely held .000050", but anything closer was pretty much hit and miss.
I gathered from the comments at Litton that they were a superb machine.

Very likely connected, then. Among other things, there is the
lapping of the record/playback/erase heads, which is likely to be done
by some of their own tools.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...

[ ... ]

[ ... passive radiator ... ]

[ ... ]

Hmm ... is there perhaps some kind of baffle to delay the sound
from the driven speaker to the passive one? But that would likely make
it peak at certain frequencies and cancel at others. (But maybe this
would happen at frequencies that those speaker elements were not fed,
being more the job of the midrange and tweeters.)

No---no baffles of any kind. I've had the woofers out of all of the
speakers to be reconed. They have a foam rim that eventually
deteriorates
and must be replaced. Heavy passages can actually tear them apart
completely, although mine have never gone that far.

I've seen that happen. A problem with pretty much *any* foam
rubber over time, and a foam rim does give significantly better
compliance than the tar-soaked paper or cloth ones with multiple pleats.


When I bought our second pair of S8R speakers, which I found listed in the
newspaper, they were being sold because of the foam failure, along with the
cabinets having been thoroughly abused. I wasn't concerned about the
woofers, knowing reconing wasn't a big issue. I was encouraged to know
that they were still the factory original foam, which was completely
different from the replacements, even from JBL. The price asked for the
speakers was a give-away for those that had an understanding of the value of
the components.

What came as a real surprise to me was when I inspected the woofers in the
Paragon. While I've been talking about them as if they have the same
speakers as they S8 system, they are really the next generation of speakers,
so their identifying numbers are different. Instead of the 375 driver for
the midrange, they use a 376. As far as I know, the chief difference is
modern magnet technology as opposed to the old Alnico technology. The 375
drivers use a 28 pound magnet, along with a 4" ribbon wound voice coil. In
JBL's literature they make reference to the 375 driver's ability to handle
explosive passages in stride. My personal experience in having owned
them since 1966 is they were too modest. Until such time that you've had
the pleasure to play with a set of these giants, I'm not sure you could
understand their capability.

[ ... ]

Great! I presume that there is no grill cloth mounted in front
of those elements.

There is a very light weight black cloth that is stretched tight and
stapled
appropriately. Doesn't seem to create any strange noises, and performs a
fairly important function of masking what's behind the wooden grills. I
think they spent enough time with the design to insure it was a good one,
but I have no way of knowing if it is, or not.

O.K. My comment was because of your mention of watching the
woofer work with heavy passages.


The front cover is easily removed. They mount with four locating plugs
that are a simple press fit. One of my methods of enjoying the system is
to watch the speakers work on heavy passages. That's more likely to occur
when I'm listening to the system instead of listening to music. You likely
understand that nuts like me enjoy their systems in more than one way.
Sometimes the music is secondary.

[ ... ]

She even searches eBay for tools for me -- and has not yet
learned to not say "this one sounds strange" and attract my attention.
:-)

How cool is that? Susan has no clue about tools, but she sure
encourages
me.

Dolores has no idea how to *use* them -- but she is good at
recognizing them. She finally found a cut-style knurler which did not
go sky high (compared to new price), and which fits my tool holders, so
I can start to experience that capability. (Well ... I do already have
one in the form of a long-armed 3-jaw chuck which works on the turret,
but that has a limited travel.

You'll have to enlighten me here, DoN. I've never used anything but the
roller type that impresses, and the old school stuff, not even a scissor
type.

Harold

Think bass reflex. Then think bass reflex with a duct to increase the
inertia of the air column. Passive radiator is the same except using
the mass of the cone instead of a duct.

Dan


Harold and Susan Vordos wrote:

[ ... passive radiator ... ]

[ ... ]




Harold

In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...

[ ... ]

No---no baffles of any kind. I've had the woofers out of all of the
speakers to be reconed. They have a foam rim that eventually
deteriorates
and must be replaced. Heavy passages can actually tear them apart
completely, although mine have never gone that far.

I've seen that happen. A problem with pretty much *any* foam
rubber over time, and a foam rim does give significantly better
compliance than the tar-soaked paper or cloth ones with multiple pleats.


When I bought our second pair of S8R speakers, which I found listed in the
newspaper, they were being sold because of the foam failure, along with the
cabinets having been thoroughly abused. I wasn't concerned about the
woofers, knowing reconing wasn't a big issue. I was encouraged to know
that they were still the factory original foam, which was completely
different from the replacements, even from JBL. The price asked for the
speakers was a give-away for those that had an understanding of the value of
the components.

Sounds good to me.

What came as a real surprise to me was when I inspected the woofers in the
Paragon. While I've been talking about them as if they have the same
speakers as they S8 system, they are really the next generation of speakers,
so their identifying numbers are different. Instead of the 375 driver for
the midrange, they use a 376. As far as I know, the chief difference is
modern magnet technology as opposed to the old Alnico technology. The 375
drivers use a 28 pound magnet, along with a 4" ribbon wound voice coil.

Hmm ... how much were they able to reduce the weight with more
modern magnet materials?

In
JBL's literature they make reference to the 375 driver's ability to handle
explosive passages in stride. My personal experience in having owned
them since 1966 is they were too modest. Until such time that you've had
the pleasure to play with a set of these giants, I'm not sure you could
understand their capability.

I'd love a chance, but probably won't get it.

[ ... ]

O.K. My comment was because of your mention of watching the
woofer work with heavy passages.


The front cover is easily removed.

O.K. So no grille cloth while you are watching. :-)

They mount with four locating plugs
that are a simple press fit. One of my methods of enjoying the system is
to watch the speakers work on heavy passages. That's more likely to occur
when I'm listening to the system instead of listening to music. You likely
understand that nuts like me enjoy their systems in more than one way.
Sometimes the music is secondary.

I understand. Sort of like sitting there and watching a shaper
cut away. Relaxing in its own right.

[ ... ]

Dolores has no idea how to *use* them -- but she is good at
recognizing them. She finally found a cut-style knurler which did not
go sky high (compared to new price), and which fits my tool holders, so
I can start to experience that capability. (Well ... I do already have
one in the form of a long-armed 3-jaw chuck which works on the turret,
but that has a limited travel.

You'll have to enlighten me here, DoN. I've never used anything but the
roller type that impresses, and the old school stuff, not even a scissor
type.

O.K. Picture the rollers ground flat on the edges without any
bevel. Mount them at an angle to the direction of cut. And mount them
so the edge, not the center, is at the centerline between the workpiece
and the screw on which the cutter rotates.

This causes the edge of the knurl to actually *cut* material away,
as it is rotated by the workpiece, instead of being embossed into the
workpiece. This produces a much sharper feeling knurl -- and does not
increase the diameter with displaced metal. I'm looking forward to
experiencing the difference once it arrives. (We're in the period
between paying and receiving at the moment.)

This requires much less force from the machine's compound, so
there is less wear on the spindle bearings and the cross-feed leadscrew.

Obviously, this kind is useless for increasing a press fit,
since it does not displace metal -- it just removes it.

The other which you mentioned, the scissors style, has the
knurls on two swing arms, with the knurls touching the workpiece at
points 180 degrees apart (typically top and bottom). A bolt with a nut
connects the two arms, either between the pivots and the knurls (as what
I have), or it connects the two arms past the pivot point (more like the
pressure point of scissors, hense the name). This still embosses the
workpiece, but the force is taken by the lever arms and the bolt, not by
the leadscrew and the spindle bearings. Thus the wear on the machine is
much less.

Another variant on that style is offered by Aloris for their
quick-change toolposts. On that one, the upper and lower knurls are
held on arms which travel on a dovetail on the front of the holder. A
leadscrew with a knurled knob at the top, and left-hand threads on one
end, and right hand threads on the other end, moves the arms
symmetrically together or apart, so once you have set the height of the
tool, you can adjust for differing workpiece diameters without having to
change the height of the tool. (The scissors style, thanks to the
pivoted arms, is self centering in use.

You've probably experienced the principle of these latter two
tools if you have a T-bar knurling tool for your lathe's turret. Again,
the force is applied to pinch the workpiece between the knurls, and the
force is all contained within the tool, instead of being applied to the
spindle bearings or the cross-feed leadscrew.

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

"DoN. Nichols" wrote in message
...
In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...
..

What came as a real surprise to me was when I inspected the woofers in
the
Paragon. While I've been talking about them as if they have the same
speakers as they S8 system, they are really the next generation of
speakers,
so their identifying numbers are different. Instead of the 375 driver
for
the midrange, they use a 376. As far as I know, the chief difference is
modern magnet technology as opposed to the old Alnico technology. The
375
drivers use a 28 pound magnet, along with a 4" ribbon wound voice coil.

Hmm ... how much were they able to reduce the weight with more
modern magnet materials?

The literature that came with the Paragon indicates the magnet assembly
weighs 10.7 kg (23-1/2 pounds), with a flux density of 15,000 gauss. It
uses a 4" diameter edge wound copper ribbon voice coil. Throat diameter of
the horn is 2".


JBL's literature they make reference to the 375 driver's ability to
handle
explosive passages in stride. My personal experience in having owned
them since 1966 is they were too modest. Until such time that you've
had
the pleasure to play with a set of these giants, I'm not sure you could
understand their capability.

I'd love a chance, but probably won't get it.

The door would be open to your visit were you to find yourself in the other
Washington.

You likely understand that nuts like me enjoy their systems in more than
one way.
Sometimes the music is secondary.

I understand. Sort of like sitting there and watching a shaper
cut away. Relaxing in its own right.

Can't add anything to that.

[ ... ]

You'll have to enlighten me here, DoN. I've never used anything but the
roller type that impresses, and the old school stuff, not even a scissor
type.

O.K. Picture the rollers ground flat on the edges without any
bevel. Mount them at an angle to the direction of cut. And mount them
so the edge, not the center, is at the centerline between the workpiece
and the screw on which the cutter rotates.

This causes the edge of the knurl to actually *cut* material away,
as it is rotated by the workpiece, instead of being embossed into the
workpiece. This produces a much sharper feeling knurl -- and does not
increase the diameter with displaced metal. I'm looking forward to
experiencing the difference once it arrives. (We're in the period
between paying and receiving at the moment.)

Thanks, DoN. I'll be interested in hearing your comments after giving the
setup a test drive. I'd probably really enjoy them, for I'm one of
those nuts that demands a perfect knurl. Even in stainless, I can turn
them out perfectly, every time. I don't like shallow knurls, preferring
them pressed to a sharp point instead. You have to get right after the
thing in stainless to avoid the work hardening potential. I can't help
but think the process of which you speak could make it much easier.


You've probably experienced the principle of these latter two
tools if you have a T-bar knurling tool for your lathe's turret.

No---never have. I've made some quite small items that got knurled, in one
case in 17-4 PH stainless. I've enjoyed success as small as 3/16" diameter.
By making a custom holder for the rolls, getting them to almost make contact
at the centerline, you can knurl very small diameter stuff. Generally the
items are far more fragile than their ability to accept the knurl, so I
start by knurling the material at the desired diameter, then machine
everything from the knurl, insuring concentricity and not damaging fragile
components. My need has always been limited, never for a production job
(I did a lot of tool making), so I always just limped by with what I had.
Makes a good machinist of you to be able to do a job without all the
foxtails and whistles, but it has a cost, too, in that it's often slower.
I've always done my best to stick with the old machining principles, right
down to not even using a DRO. In a strange, perverted sort of way, I
take great pride in that. Sure would like owning one of those scissor type
knurls, though! :-)

Harold

In article ,
Harold and Susan Vordos wrote:

"DoN. Nichols" wrote in message
...

[ ... ]

so their identifying numbers are different. Instead of the 375 driver
for
the midrange, they use a 376. As far as I know, the chief difference is
modern magnet technology as opposed to the old Alnico technology. The
375
drivers use a 28 pound magnet, along with a 4" ribbon wound voice coil.

Hmm ... how much were they able to reduce the weight with more
modern magnet materials?

The literature that came with the Paragon indicates the magnet assembly
weighs 10.7 kg (23-1/2 pounds),

O.K. A bit lighter than the older unit.

with a flux density of 15,000 gauss. It

I wonder what the flux density of the older unit was?

uses a 4" diameter edge wound copper ribbon voice coil. Throat diameter of
the horn is 2".

Very similar, apparently, other than the magnet assembly. And
the edge-wound coil would maximize the number of turns and minimize the
DC resistance, so the impedance would be more of a combination of pure
inductance and the generated back-EMF from the coil motion -- still a
rather complex mix.


JBL's literature they make reference to the 375 driver's ability to
handle
explosive passages in stride. My personal experience in having owned

[ ... ]

I'd love a chance, but probably won't get it.

The door would be open to your visit were you to find yourself in the other
Washington.

Thank you. But if I ever get back to the West coast, I am more
likely to be a lot lower, visiting my sister in Berkeley.

[ ... ]

You'll have to enlighten me here, DoN. I've never used anything but the
roller type that impresses, and the old school stuff, not even a scissor
type.

O.K. Picture the rollers ground flat on the edges without any
bevel. Mount them at an angle to the direction of cut. And mount them
so the edge, not the center, is at the centerline between the workpiece
and the screw on which the cutter rotates.

[ ... ]

Thanks, DoN. I'll be interested in hearing your comments after giving the
setup a test drive. I'd probably really enjoy them,

I suspect that you would.

for I'm one of
those nuts that demands a perfect knurl. Even in stainless, I can turn
them out perfectly, every time. I don't like shallow knurls, preferring
them pressed to a sharp point instead. You have to get right after the
thing in stainless to avoid the work hardening potential. I can't help
but think the process of which you speak could make it much easier.

Even the scissors style does a good job of knurling 416
stainless. I have made some quite sharp knurls with that -- though I
expect the cut style to make it even sharper. I haven't tried it on any
of the more difficult stainless alloys, as I have not yet needed to use
them.


You've probably experienced the principle of these latter two
tools if you have a T-bar knurling tool for your lathe's turret.

No---never have. I've made some quite small items that got knurled, in one
case in 17-4 PH stainless. I've enjoyed success as small as 3/16" diameter.
By making a custom holder for the rolls, getting them to almost make contact
at the centerline, you can knurl very small diameter stuff. Generally the
items are far more fragile than their ability to accept the knurl, so I
start by knurling the material at the desired diameter, then machine
everything from the knurl,

That makes sense. I tend to knurl before finish turning the
adjacent spots. I suspect that the cut style knurler would work well on
your tiny parts -- especially the three-armed one for turret mounting,
as the forces involved are a lot less than the standard knurling
systems.

insuring concentricity and not damaging fragile
components. My need has always been limited, never for a production job
(I did a lot of tool making), so I always just limped by with what I had.

O.K. I've needed to make some production runs (microphone
adaptors) which have made the turret really pay for itself, including
the T-bone knurling tool. (Anyway -- I collect interesting tools when I
find them (or Dolores finds them) on eBay -- just to learn how to use
them, so I can find better ways to do my projects.

Certainly a Geometric die head does a much nicer (and quicker)
job of threading brass to 5/8-27 up to a shoulder. I do it in a single
pass at about 850 RPM -- a *lot* faster than I could do it
single-pointing, even without the shoulder.

Makes a good machinist of you to be able to do a job without all the
foxtails and whistles, but it has a cost, too, in that it's often slower.
I've always done my best to stick with the old machining principles, right
down to not even using a DRO. In a strange, perverted sort of way, I
take great pride in that. Sure would like owning one of those scissor type
knurls, though! :-)

They show up from time to time -- but most of them are to
large for my machine (e.g. 1" square shanks or so), and close up in the
$500.00+ region. (Of course, new, they sell for around $1200.00 or so. :-)

Enjoy,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

I understand your preference for McIntosh Amps, but I would agree with
Ted here. I think you should go for the line level to the shop and an
amp there.
If you buy an amplifier that as not a McIntosh, I think you would have
better sound than runing 10 gauge wire from the house.

Incidently I just ran across an old article by Robert Pease on speaker
wire. He does not think much of the monster cable, but thought using
the flat cable with thirty twisted pairs paralleled might be justified.
His thought is that each pair has about a 75 ohm impedance. Thirty
pairs in parallel would have the impedance in the two ohm range.

Some of his columns are available on the Web. I will have a look to
see if this one is out there.

Dan

Harold and Susan Vordos wrote:




Thanks for the great input. Right now I'm still thinking 10 ga,
but
certainly nothing smaller. From the figures provided, it looks
like
things
get right out of control with smaller than 12 gage wire.

I still think you should go for line level to the shop and an amp
there.

I assume you have one of your amps to spare? That would surely make
it
easier! I might even overlook my zeal for owning Mc gear. :-)

I Economics drive me pretty hard, Ted. I do
appreciate and respect your comments, though. Just wish I understood
them
better.

Harold

Okay, I did look on Electronic Design Web site and while they have many
of Bob Pease's article available, they do not have this one. It is in
the May 13 1996 edition of the magazine.

On the plus side, they do have an article in the current issue on
building a TDR pulser to use with your scope.

Dan

On Sat, 12 Mar 2005 05:36:26 UTC, wrote:

I understand your preference for McIntosh Amps, but I would agree with
Ted here. I think you should go for the line level to the shop and an
amp there.

An infrared stereo headphone unit might make a nice hum-free fixed
link between house & outbuilding. Can't find the one I bought years
ago, or I'd know the answer.

If you buy an amplifier that as not a McIntosh, I think you would have
better sound than runing 10 gauge wire from the house.

That would be 10ga stranded not solid. Good quality zipcord.

Incidently I just ran across an old article by Robert Pease on speaker
wire. He does not think much of the monster cable, but thought using
the flat cable with thirty twisted pairs paralleled might be justified.
His thought is that each pair has about a 75 ohm impedance. Thirty
pairs in parallel would have the impedance in the two ohm range.

For hi-fi speaker wire the 10ga zipcord offers dozens of strands per
conductor, thus it has much greater surface area per unit length than
solid conductor would. And THIS is what you want in order to conduct
the higher audio frequencies, as they travel along the 'skin' of a
conductor. More surface area=more skin. For longer lengths thicker
than 10ga will reduce power losses. Welding cable (very flexible-
many strands) would be excellent and certainly no more expensive than
those rip-off gold plated 'monster cables'. At audible frequencies
plating conductors with silver or gold has negligible effect. Only at
rf frequencies is this needed to reduce losses.

Twisted-pair are not fine enough to achieve what good quality zip cord
can in this application. And '75 ohm characteristic impedance' has
nothing to do with power transmission.
--
sp
````


Some of his columns are available on the Web. I will have a look to
see if this one is out there.

Dan

Harold and Susan Vordos wrote:




Thanks for the great input. Right now I'm still thinking 10 ga,
but
certainly nothing smaller. From the figures provided, it looks
like
things
get right out of control with smaller than 12 gage wire.

I still think you should go for line level to the shop and an amp
there.

I assume you have one of your amps to spare? That would surely make
it
easier! I might even overlook my zeal for owning Mc gear. :-)

I Economics drive me pretty hard, Ted. I do
appreciate and respect your comments, though. Just wish I understood
them
better.

Harold

On 13 Mar 2005 00:48:06 GMT, wrote:



For hi-fi speaker wire the 10ga zipcord offers dozens of strands per
conductor, thus it has much greater surface area per unit length than
solid conductor would. And THIS is what you want in order to conduct
the higher audio frequencies, as they travel along the 'skin' of a
conductor. More surface area=more skin. For longer lengths thicker
than 10ga will reduce power losses. Welding cable (very flexible-
many strands) would be excellent and certainly no more expensive than
those rip-off gold plated 'monster cables'. At audible frequencies
plating conductors with silver or gold has negligible effect. Only at
rf frequencies is this needed to reduce losses.

Twisted-pair are not fine enough to achieve what good quality zip cord
can in this application. And '75 ohm characteristic impedance' has
nothing to do with power transmission.


Sorry to but in here, but there is a certain quantity of ******** in the
above.

Multiple strands have no effect whatsoever if they are in electrical contact.
A 3/8" diameter welding cable is essentially identical in impedance to a solid
cable of identical cross section. The only way to get multiple strands to give
you an advantage with skin effect is to insulate them from each other and to
regularly transpose the conductors so that each one ends up with the same
impedance from end to end.


Mark Rand (BSc Hons. Electrical Engineering and Electronics)
RTFM

Mark Rand wrote:
On 13 Mar 2005 00:48:06 GMT, wrote:



For hi-fi speaker wire the 10ga zipcord offers dozens of strands per
conductor, thus it has much greater surface area per unit length than
solid conductor would. And THIS is what you want in order to conduct
the higher audio frequencies, as they travel along the 'skin' of a
conductor. More surface area=more skin. For longer lengths thicker
than 10ga will reduce power losses. Welding cable (very flexible-
many strands) would be excellent and certainly no more expensive than
those rip-off gold plated 'monster cables'. At audible frequencies
plating conductors with silver or gold has negligible effect. Only at
rf frequencies is this needed to reduce losses.

Twisted-pair are not fine enough to achieve what good quality zip cord
can in this application. And '75 ohm characteristic impedance' has
nothing to do with power transmission.



Sorry to but in here, but there is a certain quantity of ******** in the
above.

Multiple strands have no effect whatsoever if they are in electrical contact.
A 3/8" diameter welding cable is essentially identical in impedance to a solid
cable of identical cross section. The only way to get multiple strands to give
you an advantage with skin effect is to insulate them from each other and to
regularly transpose the conductors so that each one ends up with the same
impedance from end to end.

I believe Bob Pease suggests the same thing. He
said that *if* skin effect is an audible issue
with speaker cables, you should take a 40 or 50
conductor ribbon cable and use the even conductors
for one channel and the odd conductors for the other.

I don't think he thought it would make any difference,
but if you wanted to do something correct from a
physics point of view that would be the best way.

In article , Mark Rand says...

Multiple strands have no effect whatsoever if they are in electrical contact.
A 3/8" diameter welding cable is essentially identical in impedance to a solid
cable of identical cross section. The only way to get multiple strands to give
you an advantage with skin effect is to insulate them from each other and to
regularly transpose the conductors so that each one ends up with the same
impedance from end to end.

Umm - yes but. At higher frequencies, the solid wire will have
*less* loss.

The reason for this is that the stranded cable has multiple contact
points between strands, and unless the individual strands are
gold plated to eliminate oxide, there will be energy loss at
each one of those contact points.

It's a skin effect thing, but with a twist.

Jim


--
==================================================
please reply to:
JRR(zero) at pkmfgvm4 (dot) vnet (dot) ibm (dot) com
==================================================