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 ---