Re: [linux-audio-user] Feasibility of Crestron like Linux BasedWholeHouse Audio System - Multisource / Multizone Capable????
5 Jan
2005
5 Jan
'05
6:30 p.m.
Guys, guys! Don't waste money on "oxygen-free" cables or other scams.
http://www.roger-russell.com/wire/wire.htm
And: if you use balanced cables (most of the soundcards mentioned, e.g. RME and Delta 1010
have balanced "tip-ring-sleeve" connections) you can have very long runs with no
audible difference. I regularly use microphone cables in excess of 1000 meters, in my job
as an audio mixer for broadcast sports, and the sound is hum-free and good enough for
broadcast. Line-level audio signals will go even further- and if you can hear or measure
a difference you have golden Bat ears.
-Steiny
(510)907-0897
----- Original Message -----
From: "Andreas Kuckartz" <A.Kuckartz(a)ping.de>
To: linux-audio-user(a)music.columbia.edu
Subject: Re: [linux-audio-user] Feasibility of Crestron like Linux BasedWholeHouse Audio
System - Multisource / Multizone Capable????
Date: 5 Jan 2005 22:43:03 +0100
Florin Andrei wrote:
--
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But it might be ok, though, to run high-
amplitude analog signal over lengthy cables. I.e., speaker signal.
At those amplitudes and impedances, there's only a very low risk of
picking up noise.
You do not pick up noise but the longer the speaker cables the higher their
capacitance and their resistance. There also are other strange distortions
happening due to cables. All of this can influence the sound:
"Speaker cable needs to have a very low electrical resistance, so
it needs to be
fairly hefty and made from a pure material, such as oxygen-free copper (OFC).
Impure material can introduce nonlinearities (the oxidised copper actually
behaves as a semiconductor) that manifest themselves as increased
distortion at
low signal levels. There are many cables that qualify, including 30A 'cooker'
mains cable, but a sensibly priced, heavy-duty speaker cable is easier to use
and looks nicer. If the cable resistance is more than a tiny
fraction of an Ohm,
the amplifier's damping factor is compromised and also the loudspeaker's
frequency response can be affected. The reason for this is that a
loudspeaker's
impedance varies with frequency, but if this impedance is placed in
series with
a significant fixed cable resistance it acts as a potential divider, and the
power delivered to the loudspeaker at different frequencies will be altered
slightly."
(http://www.soundonsound.com/sos/jan02/articles/faq0102.asp#Anchor-32729)
(It might be difficult to convince people who intend to buy expensive golden
speaker cables to use Linux and a little bit of digital hardware
instead but one
could try :-)
Cheers,
Andreas 
5 Jan
5 Jan
7:20 p.m.
New subject: [linux-audio-user] Feasibility of Crestron like Linux BasedWholeHouse Audio System - Multisource / Multizone Capable????
On Wednesday 05 January 2005 22:30, Eric Steinberg wrote:
Guys, guys! Don't waste money on
"oxygen-free" cables or other scams.
http://www.roger-russell.com/wire/wire.htm
And: if you use balanced cables (most of the soundcards mentioned, e.g. RME
and Delta 1010 have balanced "tip-ring-sleeve" connections) you can have
very long runs with no audible difference. I regularly use microphone
cables in excess of 1000 meters, in my job as an audio mixer for broadcast
sports, and the sound is hum-free and good enough for broadcast.
Line-level audio signals will go even further- and if you can hear or
measure a difference you have golden Bat ears.
-Steiny
And lets blow away the importance of "Damping Factor" while we're at it...
Consider that there is a voice coil in series with that cable and that it is
made of comparatively fine ware and will have a real resistance of a few
ohms! Obviously the impedance at audio frequencies is higher but at DC it
will probably meter to 3-6 ohms or so (This is also highly variable as the
coil heats up in operation).
Now given that this is a resistance that is in series with the cable, and the
output impedance of the amplifier, remind me how exactly any damping factor
greater then about 20 is supposed to matter?
Ok so there is (possibly) a crossover in there somewhere, but IMHO that is a
detail.
Regards, Dan.
7:37 p.m.
New subject: [linux-audio-user] Feasibility of Crestron like Linux BasedWholeHouse Audio System - Multisource / Multizone Capable????
On Wed, Jan 05, 2005 at 05:30:38PM -0500, Eric Steinberg wrote:
Guys, guys! Don't waste money on
"oxygen-free" cables or other scams.
Panic not! He wasn't advocating "golden ears" cables!
By the way most people don't know that ALL cables are made from
oxygen-free copper. There's nothing unusual about it.
My own theory about how people might hear an improvement when they
"upgrade" their cable is that in the process of unplugging the old and
plugging in the new, they give the contacts a much-needed cleaning!
(I like to use two-core power cable for my speakers, 6amp or 10amp)
--
Anahata
anahata(a)treewind.co.uk -+- http://www.treewind.co.uk
Home: 01638 720444 Mob: 07976 263827
6 Jan
6 Jan
12:17 p.m.
New subject: Voodoo (Re: [linux-audio-user] Feasibility of Crestron like LinuxBasedWholeHouse Audio System - Multisource / Multizone Capable????)
Eric Steinberg wrote:
Guys, guys! Don't waste money on
"oxygen-free" cables or other scams.
http://www.roger-russell.com/wire/wire.htm
Thanks a lot for that link!
I know that a lot of voodoo magic is spread (and sold) by sections of the audio
electronics industry. I had hoped that "Sound On Sound" could be trusted. I
will
send them the link and ask them for an explanation. To their credit they only
suggest to buy and use 30A 'cooker' mains cable" or "sensibly priced,
heavy-duty
speaker cable" - which does not really differ from the suggestions of Roger
Russell.
OT: If German readers are interested in a collection of home audio crap they
should have a look at this years January issue of "stereoplay". They have an
article about "sound differences" which allegedly result from using different
brands of writeable CD-Rs. They do not even try to explain why there could be
any sound differences at all. While printing a separate article about errors
which can be measured by certain test devices they do not even mention error
correction and error concealment (which are part of CD-technology since its
beginning). The funny thing is that they also print measurements of not
correctable E32 errors for both the expensive brand and a cheap one. Both are
visually undistinguishable close to 0 ! Another "test"-article is about bowls
made of gold or platin (the best according to the "test" are of cause the ones
made of platin which are twice as expensive as those made of gold. And one
should use not only one but several of those bowls,
http://www.fastaudio.com/INT/acsys100.html) And last but not least they run a
speaker cables-"test" on five pages in the same issue...
Cheers,
Andreas
----- Original Message -----
From: "Andreas Kuckartz" <A.Kuckartz(a)ping.de>
To: linux-audio-user(a)music.columbia.edu
Subject: Re: [linux-audio-user] Feasibility of Crestron like Linux
BasedWholeHouse
Audio System - Multisource / Multizone Capable????
Date: 5 Jan 2005 22:43:03 +0100
>
> Florin Andrei wrote:
>
> > But it might be ok, though, to run high-
> > amplitude analog signal over lengthy cables. I.e., speaker signal.
> > At those amplitudes and impedances, there's only a very low risk of
> > picking up noise.
>
> You do not pick up noise but the longer the speaker cables the higher their
> capacitance and their resistance. There also are other strange distortions
> happening due to cables. All of this can influence the sound:
>
> "Speaker cable needs to have a very low electrical resistance, so
> it needs to be
> fairly hefty and made from a pure material, such as oxygen-free copper
(OFC).
> Impure material can introduce nonlinearities (the
oxidised copper actually
> behaves as a semiconductor) that manifest themselves as increased
> distortion at
> low signal levels. There are many cables that qualify, including 30A
'cooker'
> mains cable, but a sensibly priced, heavy-duty
speaker cable is easier to
use
and looks
nicer. If the cable resistance is more than a tiny
fraction of an Ohm,
the amplifier's damping factor is compromised and also the loudspeaker's
frequency response can be affected. The reason for this is that a
loudspeaker's
impedance varies with frequency, but if this impedance is placed in
series with
a significant fixed cable resistance it acts as a potential divider, and the
power delivered to the loudspeaker at different frequencies will be altered
slightly."
(http://www.soundonsound.com/sos/jan02/articles/faq0102.asp#Anchor-32729)
(It might be difficult to convince people who intend to buy expensive golden
speaker cables to use Linux and a little bit of digital hardware
instead but one
could try :-)
Cheers,
Andreas
--
___________________________________________________________
Sign-up for Ads Free at Mail.com
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7 Jan
7 Jan
11:39 a.m.
New subject: [linux-audio-user] Feasibility of Crestron like LinuxBasedWholeHouse Audio System - Multisource / Multizone Capable????
Today on /.
http://www.linuxdevices.com/articles/AT7647366603.html
A linux based wireless music distribution system.
FYI,
-ry
7308
days inactive
7310
days old
linux-audio-user@lists.linuxaudio.org
4 comments
5 participants
participants (5)
-
anahata -
Andreas Kuckartz -
Dan Mills -
Eric Steinberg -
Ryan Gallagher