I'm helping a friend make changes to his audio-video system, principally
moving a main AV equipment rack to a different location. This involves
rerouting a good deal of speaker wiring, almost all of it running in the
loft under insulation and in some areas chipboard flooring.

The "correct" way would be to uncover the existing cables and relocate them.
Given the necessary disruption and severely limited headroom, a far more
attractive idea is to connect new cables to the accessible ends of the
current ones and run them across the top of the loft floors and areas of
exposed insulation then down through to ceiling to a new AV hub.

The maximum extension would be in the region of sixteen feet, resulting in a
cable run some thirty feet from amplifier to loudspeaker; would that make
any material difference to the sound or the loading on the amp? This is a
decent mid-price hifi setup but nothing really ultra-high-end.

We can of course experiment with extending the cables on just a pair of
speakers in order to assess the sound, but it would be useful to know in
advance if a run of such a length is pushing things a bit.

Many thanks.

So much depends on the speakers and amp in use. I've heard amps that seem to
sound leaden on long speaker runs, which I'd consider bad design really. I
think the best you can do is use decent cables, ie that can handle the
current and suck it and see. I'd have thought in the current state of the
art all these strange effects should be sorted out by now. My one issue
would be pick up of interference being fed back to the amp. I had an issue
with the local Sea Cadets some time ago, but never did get it sorted even
with ferrite beads. I sold the amp and got a different make and there was no
issue. One of the problems of having too wide a bandwidth and long cables.
Brian

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"Bert Coules" wrote in message
o.uk...
I'm helping a friend make changes to his audio-video system, principally
moving a main AV equipment rack to a different location. This involves
rerouting a good deal of speaker wiring, almost all of it running in the
loft under insulation and in some areas chipboard flooring.

The "correct" way would be to uncover the existing cables and relocate
them. Given the necessary disruption and severely limited headroom, a far
more attractive idea is to connect new cables to the accessible ends of
the current ones and run them across the top of the loft floors and areas
of exposed insulation then down through to ceiling to a new AV hub.

The maximum extension would be in the region of sixteen feet, resulting in
a cable run some thirty feet from amplifier to loudspeaker; would that
make any material difference to the sound or the loading on the amp? This
is a decent mid-price hifi setup but nothing really ultra-high-end.

We can of course experiment with extending the cables on just a pair of
speakers in order to assess the sound, but it would be useful to know in
advance if a run of such a length is pushing things a bit.

Many thanks.

Brian,

Thanks for that. The existing cabling is hefty (and expensive-looking)
specialist speaker wiring: matching it exactly for new runs is going to be
pretty pricey, not that that's necessarily a problem, but it's also pretty
inflexible. I might suggest experimenting with something of similar weight
but easier to work with: if it functions OK for the longest necessary run
then it should be fine for the rest, if my friend is willing to ignore the
extreme high-end audiophile insistence on having all speaker cables the same
length.

The possibility of picking up radiated interference hadn't occurred to me at
all: that would liven up his listening no end.

On Thursday, 2 January 2020 08:44:28 UTC, Bert Coules wrote:
The maximum extension would be in the region of sixteen feet, resulting in a
cable run some thirty feet from amplifier to loudspeaker

10 metres is nothing for any reasonable amp, speakers and sensible cable.

Owain

On Thu, 2 Jan 2020 09:07:57 -0000, Bert Coules wrote:

The existing cabling is hefty (and expensive-looking) specialist speaker
wiring: matching it exactly for new runs is going to be pretty pricey,
not that that's necessarily a problem, but it's also pretty inflexible.

It really depends on how much power you need to shift to the speakers
and how much electrical damping the speakers require.

Is this just for "background music" or to have 110 dB SPL flat 20 Hz
to 20 kHz cinema/disco "sound experience"?

From personal experience changing 5 m speaker leads from 72 strand
"heavy duty bell wire" to 1024 strand 2.5 mm^2 "speaker cable" made a
noticeable difference to the bottom end when driven hard. The bass
was much tighter and controlled as the lower cable resistance
electrically damped the 10" paper cone woofers much better. The
voltage drop along each wire went from 5 or 6 V to less than 2, with
100W RMS being delivered to the speakers.

If I was putting in a "whole house system" I'd either go for active
speakers or an amp with sperate speakers (on decent cable...) in each
room and distrubute at line level balanced not speaker level.
Amp/speakers is probably more convient to control.

--
Cheers
Dave.

Dave,

For some reason the centre of your message appears as blank white space on
my screen, but enough remains legible to get your points, I think. I don't
know the full tech details of the installation but I do know that the
speakers are part of a home cinema setup: three front, two side, two rear,
and a separate subwoofer. The amp is a fairly high-end domestic Marantz.
Not sure about the speakers.

Owain,

10 metres is nothing for any reasonable amp, speakers and sensible cable.

Thanks.

On 02/01/2020 13:38, Bert Coules wrote:
Dave,

For some reason the centre of your message appears as blank white space
on my screen, but enough remains legible to get your points, I think.Â* I
don't know the full tech details of the installation but I do know that
the speakers are part of a home cinema setup: three front, two side, two
rear, and a separate subwoofer.Â* The amp is a fairly high-end domestic
Marantz. Not sure about the speakers.



If messages appear odd it's worth looking at Google Groups

https://groups.google.com/d/msg/uk.d...Q/0krJNYDABgAJ





--
Robin
reply-to address is (intended to be) valid

On 02/01/2020 08:44, Bert Coules wrote:
I'm helping a friend make changes to his audio-video system, principally
moving a main AV equipment rack to a different location.Â* This involves
rerouting a good deal of speaker wiring, almost all of it running in the
loft under insulation and in some areas chipboard flooring.

The "correct" way would be to uncover the existing cables and relocate
them. Given the necessary disruption and severely limited headroom, a
far more attractive idea is to connect new cables to the accessible ends
of the current ones and run them across the top of the loft floors and
areas of exposed insulation then down through to ceiling to a new AV hub.

The maximum extension would be in the region of sixteen feet, resulting
in a cable run some thirty feet from amplifier to loudspeaker; would
that make any material difference to the sound or the loading on the
amp?Â* This is a decent mid-price hifi setup but nothing really
ultra-high-end.

We can of course experiment with extending the cables on just a pair of
speakers in order to assess the sound, but it would be useful to know in
advance if a run of such a length is pushing things a bit.

Many thanks.
It will loosen the bass slightly. Use very fat cables


--
"When one man dies it's a tragedy. When thousands die it's statistics."

Josef Stalin

Yes I have a sub woofer here with internal amp which used to pick up Radio
China till a friend put in some capacitors to stop it. It was coming in via
the input terminals. Bah humbug.
There is of course a person who makes loads of money out of unproven audio
cables called Russ Andrews who seems to make unsubstantiated claims for
anything he sells at huge mark ups.
To me this is a simple LF transmission line issue. So the losses matter
since the amp low impedance needs to be seen by the speaker to make them
have the right damping. Apart from that, all this talk of oxygen free and
the like is fiddling about at the edges of things.

Brian

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"Bert Coules" wrote in message
o.uk...
Brian,

Thanks for that. The existing cabling is hefty (and expensive-looking)
specialist speaker wiring: matching it exactly for new runs is going to be
pretty pricey, not that that's necessarily a problem, but it's also pretty
inflexible. I might suggest experimenting with something of similar
weight but easier to work with: if it functions OK for the longest
necessary run then it should be fine for the rest, if my friend is willing
to ignore the extreme high-end audiophile insistence on having all speaker
cables the same length.

The possibility of picking up radiated interference hadn't occurred to me
at all: that would liven up his listening no end.

Yes well, he did say it was not top of the line, and as such I think most
cables with a decent low resistance are probably OK.
The effect you mention on bass is one reason why so many sub woofers have
their own inbuilt amplifiers I'd suggest.
The problem with active speakers fed wirelessly is you still need a mains
supply and as such you then need wires for that instead!
Brian

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"Dave Liquorice" wrote in message
idual.net...
On Thu, 2 Jan 2020 09:07:57 -0000, Bert Coules wrote:

The existing cabling is hefty (and expensive-looking) specialist speaker
wiring: matching it exactly for new runs is going to be pretty pricey,
not that that's necessarily a problem, but it's also pretty inflexible.

It really depends on how much power you need to shift to the speakers
and how much electrical damping the speakers require.

Is this just for "background music" or to have 110 dB SPL flat 20 Hz
to 20 kHz cinema/disco "sound experience"?

From personal experience changing 5 m speaker leads from 72 strand
"heavy duty bell wire" to 1024 strand 2.5 mm^2 "speaker cable" made a
noticeable difference to the bottom end when driven hard. The bass
was much tighter and controlled as the lower cable resistance
electrically damped the 10" paper cone woofers much better. The
voltage drop along each wire went from 5 or 6 V to less than 2, with
100W RMS being delivered to the speakers.

If I was putting in a "whole house system" I'd either go for active
speakers or an amp with sperate speakers (on decent cable...) in each
room and distrubute at line level balanced not speaker level.
Amp/speakers is probably more convient to control.

--
Cheers
Dave.

His message was OK here, must be something on the client you are using.
Is the sub amplified in its own right?
Brian

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"Bert Coules" wrote in message
o.uk...
Dave,

For some reason the centre of your message appears as blank white space on
my screen, but enough remains legible to get your points, I think. I
don't know the full tech details of the installation but I do know that
the speakers are part of a home cinema setup: three front, two side, two
rear, and a separate subwoofer. The amp is a fairly high-end domestic
Marantz. Not sure about the speakers.

Yes but as all Usenet messages are plain text there seems no reason for any
one particular message to be an issue, unless the client is having issues of
some type.
Brian

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"Robin" wrote in message
...
On 02/01/2020 13:38, Bert Coules wrote:
Dave,

For some reason the centre of your message appears as blank white space
on my screen, but enough remains legible to get your points, I think. I
don't know the full tech details of the installation but I do know that
the speakers are part of a home cinema setup: three front, two side, two
rear, and a separate subwoofer. The amp is a fairly high-end domestic
Marantz. Not sure about the speakers.



If messages appear odd it's worth looking at Google Groups

https://groups.google.com/d/msg/uk.d...Q/0krJNYDABgAJ





--
Robin
reply-to address is (intended to be) valid

Most people with surround set ups spend more time deciding which profile
they should use for each track, than listening to it. Ahem.
Brian

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"Bert Coules" wrote in message
o.uk...
Owain,

10 metres is nothing for any reasonable amp, speakers and sensible cable.

Thanks.

And make the joins accessible for goodness sake. I used to find soldering
them together beat most other ways generally, but of course make sure they
don't short.
Keep out of reach of Squirrels too.
Brian

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Note this Signature is meaningless.!
"The Natural Philosopher" wrote in message
...
On 02/01/2020 08:44, Bert Coules wrote:
I'm helping a friend make changes to his audio-video system, principally
moving a main AV equipment rack to a different location. This involves
rerouting a good deal of speaker wiring, almost all of it running in the
loft under insulation and in some areas chipboard flooring.

The "correct" way would be to uncover the existing cables and relocate
them. Given the necessary disruption and severely limited headroom, a far
more attractive idea is to connect new cables to the accessible ends of
the current ones and run them across the top of the loft floors and areas
of exposed insulation then down through to ceiling to a new AV hub.

The maximum extension would be in the region of sixteen feet, resulting
in a cable run some thirty feet from amplifier to loudspeaker; would that
make any material difference to the sound or the loading on the amp? This
is a decent mid-price hifi setup but nothing really ultra-high-end.

We can of course experiment with extending the cables on just a pair of
speakers in order to assess the sound, but it would be useful to know in
advance if a run of such a length is pushing things a bit.

Many thanks.
It will loosen the bass slightly. Use very fat cables


--
"When one man dies it's a tragedy. When thousands die it's statistics."

Josef Stalin

On 02/01/2020 08:44, Bert Coules wrote:
I'm helping a friend make changes to his audio-video system, principally
moving a main AV equipment rack to a different location.Â* This involves
rerouting a good deal of speaker wiring, almost all of it running in the
loft under insulation and in some areas chipboard flooring.

The "correct" way would be to uncover the existing cables and relocate
them. Given the necessary disruption and severely limited headroom, a
far more attractive idea is to connect new cables to the accessible ends
of the current ones and run them across the top of the loft floors and
areas of exposed insulation then down through to ceiling to a new AV hub.

The maximum extension would be in the region of sixteen feet, resulting
in a cable run some thirty feet from amplifier to loudspeaker; would
that make any material difference to the sound or the loading on the
amp?Â* This is a decent mid-price hifi setup but nothing really
ultra-high-end.

We can of course experiment with extending the cables on just a pair of
speakers in order to assess the sound, but it would be useful to know in
advance if a run of such a length is pushing things a bit.

Many thanks.

I got involved with the audio system in a big old house that was being
renovated. I can't remember what sorts of amp and speakers it was but
the speakers were big buggers that weighed a ton and were on wheels and
the amp was a monster thing. Actually there was a pre-amp feeding two
black boxes that had fans. For some stupid reason the amps had to be in
a little room that was at one end of a gigantic long room and the
speakers were at the other end of this big room. The cable route had to
be circuitous. I used 81 strand auto cable. Bought two 100m drums, one
red and one black, and made up lengths of 'twin' feeder. The speakers
had great big binding posts for connectors, which was fine. The
connections to the amps were a bit faffy though. It all sounded
absolutely fine when it was done and it was incredibly loud. I played
some fairground organ music and it sounded awesome.

Bill

Curiously, when I went to respond to the partially-blank message it was
reproduced complete and intact in the reply box. Possibly a glitch at my
end, I think.

The subwoofer in the installation in question is indeed powered.

Brian Gaff wrote:

And make the joins accessible for goodness sake.

Yes, that should be possible. And so should soldering, which I know is the
ideal method. On that topic, can heat-shrink sleeving be tightened with a
hair dryer on a high setting? Neither of us has a hot-air gun and I've
never had much success with matches or a lighter.

Keep out of reach of Squirrels too.

Undoubtedly a valuable piece of advice for life in general.

Thanks for that, Bill. This setup is considerably more modest, but sounded
good to me in its current layout and hopefully will do so again once we've
finished shifting bits of it about.

On Thursday, 2 January 2020 20:35:22 UTC, Bert Coules wrote:
can heat-shrink sleeving be tightened with a
hair dryer on a high setting?

Yes.

Owain

On 02/01/2020 20:12, Bill Wright wrote:
On 02/01/2020 08:44, Bert Coules wrote:
I'm helping a friend make changes to his audio-video system,
principally moving a main AV equipment rack to a different location.
This involves rerouting a good deal of speaker wiring, almost all of
it running in the loft under insulation and in some areas chipboard
flooring.

The "correct" way would be to uncover the existing cables and relocate
them. Given the necessary disruption and severely limited headroom, a
far more attractive idea is to connect new cables to the accessible
ends of the current ones and run them across the top of the loft
floors and areas of exposed insulation then down through to ceiling to
a new AV hub.

The maximum extension would be in the region of sixteen feet,
resulting in a cable run some thirty feet from amplifier to
loudspeaker; would that make any material difference to the sound or
the loading on the amp?Â* This is a decent mid-price hifi setup but
nothing really ultra-high-end.

We can of course experiment with extending the cables on just a pair
of speakers in order to assess the sound, but it would be useful to
know in advance if a run of such a length is pushing things a bit.

Many thanks.

I got involved with the audio system in a big old house that was being
renovated. I can't remember what sorts of amp and speakers it was but
the speakers were big buggers that weighed a ton and were on wheels and
the amp was a monster thing. Actually there was a pre-amp feeding two
black boxes that had fans. For some stupid reason the amps had to be in
a little room that was at one end of a gigantic long room and the
speakers were at the other end of this big room. The cable route had to
be circuitous. I used 81 strand auto cable. Bought two 100m drums, one
red and one black, and made up lengths of 'twin' feeder. The speakers
had great big binding posts for connectors, which was fine. The
connections to the amps were a bit faffy though. It all sounded
absolutely fine when it was done and it was incredibly loud. I played
some fairground organ music and it sounded awesome.

Bill

Apart from flexibility, does 81 strand auto cable have any advantage
over (say) 6mm^2 singles?

On Thursday, 2 January 2020 08:44:28 UTC, Bert Coules wrote:
I'm helping a friend make changes to his audio-video system, principally
moving a main AV equipment rack to a different location. This involves
rerouting a good deal of speaker wiring, almost all of it running in the
loft under insulation and in some areas chipboard flooring.

The "correct" way would be to uncover the existing cables and relocate them.
Given the necessary disruption and severely limited headroom, a far more
attractive idea is to connect new cables to the accessible ends of the
current ones and run them across the top of the loft floors and areas of
exposed insulation then down through to ceiling to a new AV hub.

The maximum extension would be in the region of sixteen feet, resulting in a
cable run some thirty feet from amplifier to loudspeaker; would that make
any material difference to the sound or the loading on the amp? This is a
decent mid-price hifi setup but nothing really ultra-high-end.

We can of course experiment with extending the cables on just a pair of
speakers in order to assess the sound, but it would be useful to know in
advance if a run of such a length is pushing things a bit.

Many thanks.

1 sqmm cable is 44mohm/m, so 16ft 5m = 0.22 ohms. No problem! Even junk grade 0.25sqmm would only be 0.88 ohms.


NT

Precisely: if the Usenet client (or server) is mangling a message then
the browser and Google Groups offer a second chance.

On 02/01/2020 20:01, Brian Gaff (Sofa 2) wrote:
Yes but as all Usenet messages are plain text there seems no reason for any
one particular message to be an issue, unless the client is having issues of
some type.
Brian



--
Robin
reply-to address is (intended to be) valid

On Thu, 2 Jan 2020 19:58:42 -0000, Brian Gaff \(Sofa 2\) wrote:

The problem with active speakers fed wirelessly is you still need a
mains supply and as such you then need wires for that instead!

Who said anything about wireless active speakers? I mentioned the
distribution being balanced line level... B-)

--
Cheers
Dave.

On Thu, 2 Jan 2020 13:08:49 -0800 (PST), wrote:

1 sqmm cable is 44mohm/m, so 16ft 5m = 0.22 ohms. No problem!

Per leg, two legs = 0.44 ohms = 5.5% of a nominal 8 ohm speaker
impedance.
Not a problem for low level background music but for a half decent
5.1 setup running at cimematic volumes it'll be having an effect on
the speaker damping.

There was nothing obviously "wrong" with my system when using 72
strand bell wire but the change to 2.5 mm^2 stuff really did make a
marked improvement to the bass.

--
Cheers
Dave.

"Bert Coules" Wrote in message:
Brian Gaff wrote:

And make the joins accessible for goodness sake.

Yes, that should be possible. And so should soldering, which I know is the
ideal method. On that topic, can heat-shrink sleeving be tightened with a
hair dryer on a high setting? Neither of us has a hot-air gun and I've
never had much success with matches or a lighter.

Keep out of reach of Squirrels too.

Undoubtedly a valuable piece of advice for life in general.



Stagger the joints and the potential for shorts is hugely decreased...
--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

"Dave Liquorice" wrote in
idual.net:

On Thu, 2 Jan 2020 13:08:49 -0800 (PST), wrote:

1 sqmm cable is 44mohm/m, so 16ft 5m = 0.22 ohms. No problem!

Per leg, two legs = 0.44 ohms = 5.5% of a nominal 8 ohm speaker
impedance.
Not a problem for low level background music but for a half decent
5.1 setup running at cimematic volumes it'll be having an effect on
the speaker damping.

There was nothing obviously "wrong" with my system when using 72
strand bell wire but the change to 2.5 mm^2 stuff really did make a
marked improvement to the bass.


Meanwhile, the younger generation think Alexa sound great.

On 02/01/2020 21:01, newshound wrote:

Apart from flexibility, does 81 strand auto cable have any advantage
over (say) 6mm^2 singles?

I shouldn't think so. I just wanted something flexible.

Bill

In article ,
Brian Gaff \(Sofa 2\) wrote:
Yes I have a sub woofer here with internal amp which used to pick up
Radio China till a friend put in some capacitors to stop it. It was
coming in via the input terminals. Bah humbug.

Pretty unlikely to happen between power amp and speaker, though.

--
*According to my calculations, the problem doesn't exist.

Dave Plowman London SW
To e-mail, change noise into sound.

On 02/01/2020 20:41, wrote:
On Thursday, 2 January 2020 20:35:22 UTC, Bert Coules wrote:
can heat-shrink sleeving be tightened with a
hair dryer on a high setting?

Yes.

Owain


A *carefully* applied match will do the same.

On 03/01/2020 14:45, Andrew wrote:
On 02/01/2020 20:41, wrote:
On Thursday, 2 January 2020 20:35:22 UTC, Bert CoulesÂ* wrote:
can heat-shrink sleeving be tightened with a
hair dryer on a high setting?

A *carefully* applied match will do the same.

Can't you just put it near a radiant ring on a cooker?

--
Max Demian

Max Demian wrote:

Can't you just put it near a radiant ring on a cooker?

Sadly, due to an inexplicable design oversight, there are no radiant rings
in my loft.