7 Feb
2004
7 Feb
'04
7:49 a.m.
hi everyone!
we are moving houses in a month, and i'm planning to install some
decent cabling thoughout our new flat. begone, ye maze of twisty
little cables all alike :)
the idea is to run an eight-way symmetric audio multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp
cables carrying 10/100/1000baseTX ethernet in the same cable duct
over a length of about 15-20 meters.
will this lead to problems in the audio signal?
my naive hope is that since all garbage radiating from the ethernet
will be well outside the audible range it might be ok. but then
there's always the chance of something demodulating it into the
20-20k range...
does anyone here have experience with such a setup?
any hints, success and/or horror stories welcome.
jörn
--
"I never use EQ, never, never, never. I previously used to use mic
positioning but I've even given up on that too."
- Jezar on http://www.audiomelody.com
Jörn Nettingsmeier
Kurfürstenstr 49, 45138 Essen, Germany
http://spunk.dnsalias.org (my server)
http://www.linuxaudiodev.org (Linux Audio Developers)
7 Feb
7 Feb
11:35 a.m.
On Sat, Feb 07, 2004 at 12:45:03PM +0100, Joern Nettingsmeier wrote:
the idea is to run an eight-way symmetric audio
multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp
cables carrying 10/100/1000baseTX ethernet in the same cable duct
over a length of about 15-20 meters.
will this lead to problems in the audio signal?
Twisted pair ethernet is a balanced signal so should radiate little. If
your audio system is balanced too that will help.
With three shields between the audio and the ethernet twisted pair I
doubt if you'll experience problems. You don't mention whether the audio
cable will be carrying microphone signals or only line level - that
makes a big difference!
If you're really paranoid you could use star-quad audio cable. That has
four cores instead of two and much better inference rejection than
twisted pair.
--
Anahata
anahata(a)treewind.co.uk -+- http://www.treewind.co.uk
Home: 01638 720444 Mob: 07976 263827
5:35 p.m.
New subject: [linux-audio-user] cabling question: crosstalk between audio and cat5 ethernet?
Anahata wrote:
On Sat, Feb 07, 2004 at 12:45:03PM +0100, Joern
Nettingsmeier wrote:
mostly microphone unfortunately.
the idea is to run an eight-way symmetric audio
multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp
cables carrying 10/100/1000baseTX ethernet in the same cable duct
over a length of about 15-20 meters.
will this lead to problems in the audio signal?
Twisted pair ethernet is a balanced signal so should radiate little. If
your audio system is balanced too that will help.
With three shields between the audio and the ethernet twisted pair I
doubt if you'll experience problems. You don't mention whether the audio
cable will be carrying microphone signals or only line level - that
makes a big difference! If you're really paranoid you could use star-quad
audio cable. That has
four cores instead of two and much better inference rejection than
twisted pair.
hmm. i wonder how that works? anyway, four-core cables are probably
too expensive for me.
--
"I never use EQ, never, never, never. I previously used to use mic
positioning but I've even given up on that too."
- Jezar on http://www.audiomelody.com
Jörn Nettingsmeier
Kurfürstenstr 49, 45138 Essen, Germany
http://spunk.dnsalias.org (my server)
http://www.linuxaudiodev.org (Linux Audio Developers)
5:48 p.m.
New subject: [linux-audio-user] cabling question: crosstalk between audio and cat5 ethernet?
Joern Nettingsmeier wrote:
Anahata wrote:
like joern says, make sure they're balanced audio cables.
On Sat, Feb 07, 2004 at 12:45:03PM +0100, Joern
Nettingsmeier wrote:
mostly microphone unfortunately. the idea is to run an eight-way symmetric audio
multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp
cables carrying 10/100/1000baseTX ethernet in the same cable duct
over a length of about 15-20 meters.
will this lead to problems in the audio signal?
Twisted pair ethernet is a balanced signal so should radiate little. If
your audio system is balanced too that will help.
With three shields between the audio and the ethernet twisted pair I
doubt if you'll experience problems. You don't mention whether the audio
cable will be carrying microphone signals or only line level - that
makes a big difference!
5:49 p.m.
New subject: [linux-audio-user] cabling question: crosstalk between audio and cat5 ethernet?
Twisted pair
ethernet is a balanced signal so should radiate little. If
your audio system is balanced too that will help.
With three shields between the audio and the ethernet twisted pair I
doubt if you'll experience problems. You don't mention whether the audio
cable will be carrying microphone signals or only line level - that
makes a big difference!
mostly microphone unfortunately.
6:18 p.m.
On 02/07/04 21:31:19, Joern Nettingsmeier wrote:
Just a little more expensive. Broadcast supply houses typically sub-
contract cable orders to a made-to-order cable house, so there's no
time penalty associated with specifying brand and model for both
connectors and cable; custom cables typically ship within a week of the
order. A decent cable house should be able to supply star-quad cable,
and the price should be perhaps ten or twenty percent more per foot
than cable with only a single twisted pair. Either way, the connectors
(XLR or phone plug) are the same.
RLH
If you're
really paranoid you could use star-quad audio cable. That
has four cores instead of two and much better inference rejection
than twisted pair.
hmm. i wonder how that works? anyway, four-core cables are probably
too expensive for me.
8 Feb
8 Feb
2:25 p.m.
New subject: [linux-audio-user] cabling question: crosstalk between audio and cat5 ethernet?
On Sat, Feb 07, 2004 at 10:31:19PM +0100, Joern Nettingsmeier wrote:
mostly microphone unfortunately.
My wild guess is that you'll be OK anyway.
hmm. i wonder how that works? anyway, four-core cables
are probably
too expensive for me.
The use of the cores is like this:
+ -
- +
Tying opposite pairs together like that means that even a very localized
magnetic field induces virtually no voltage between the wires, without
relying on the averaging effect of twisting the wires.
Four core mic cable costs more that the two core equivalent, but you
could try any general purpose 4 core cable. It doesn't have to be very
flexible and mechanically noise-free like specialist mic cable usually
is, as it will be permanently installed.
--
Anahata
anahata(a)treewind.co.uk -+- http://www.treewind.co.uk
Home: 01638 720444 Mob: 07976 263827
2:40 p.m.
On 02/08/04 18:21:15, Anahata wrote:
Four core mic cable costs more that the two core
equivalent, but you
could try any general purpose 4 core cable. It doesn't have to be
very flexible and mechanically noise-free like specialist mic cable
usually is, as it will be permanently installed.
Here in the states, so-called "star-quad" microphone cable can be had
in bulk for about a half-dollar a foot (a thousand-foot spool for just
over $500). This is flexible, shielded, jacketed cable, 24 AWG by
Belden.
Here's a link to a broadcast supply house; look under "audio cable and
wiring": http://www.bswusa.com/
RLH
7 Feb
7 Feb
5:12 p.m.
On Sat, Feb 07, 2004 at 12:45:03 +0100, Joern Nettingsmeier wrote:
the idea is to run an eight-way symmetric audio
multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp
cables carrying 10/100/1000baseTX ethernet in the same cable duct
over a length of about 15-20 meters.
will this lead to problems in the audio signal?
As somone else pointed out ethernet is also balanced, I have plenty of
busy ethernet near my audio cable rats-nest and I've not noticed any
problems from it.
- Steve
8 Feb
8 Feb
8:02 a.m.
the idea is to run an eight-way symmetric audio
multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp
cables carrying 10/100/1000baseTX ethernet in the same cable duct
over a length of about 15-20 meters.
The only thing I'd have to add is that multicore is not actually
designed to be used with microphones and mixers - it's a bit flimsy
for that, as an XLR plug is designed for a much fatter individual
cables. It's actually designed for those rectangular multiway plugs
with lots of pins.
If I was rebuilding my studio from scratch, I'd use full sized cable
with braided shielding for all the looms. (The multicore was already
installed by the time I moved in). It might need bigger ducting, but
I suspect the interference rejection once the loom has been split
into individual wires would be much greater.
You don't need to have the wires outside of the outer shielding with a
multiway plug, but if you have a mixer with XLRs or a patch panel...
Cheers
Daniel
8:31 a.m.
New subject: [linux-audio-user] cabling question: crosstalk between audio and cat5 ethernet?
thanks to everyone who responded!
after hearing your opinions, i think i'll go ahead and run both
audio and cat5 in the same duct.
i will do the soldering myself - if i can get hold of a multicore
with quad configuration for an affordable price, i'll try it.
david's suggestion to use individual cables makes sense, but would
require very large holes through the walls, so i'll go with a
multicore instead.
the audio cable will run between two xlr breakout boxes, so the loom
and shielding problem david hinted at will not be an issue.
i'll let you know how/if it works out eventually...
best,
jörn
Joern Nettingsmeier wrote:
hi everyone!
we are moving houses in a month, and i'm planning to install some decent
cabling thoughout our new flat. begone, ye maze of twisty little cables
all alike :)
the idea is to run an eight-way symmetric audio multicore (shielded
pairs and an outer foil shield as well) along with 4x cat5 s/stp cables
carrying 10/100/1000baseTX ethernet in the same cable duct over a length
of about 15-20 meters.
will this lead to problems in the audio signal?
my naive hope is that since all garbage radiating from the ethernet will
be well outside the audible range it might be ok. but then there's
always the chance of something demodulating it into the 20-20k range...
does anyone here have experience with such a setup?
any hints, success and/or horror stories welcome.
jörn
--
"I never use EQ, never, never, never. I previously used to use mic
positioning but I've even given up on that too."
- Jezar on http://www.audiomelody.com
Jörn Nettingsmeier
Kurfürstenstr 49, 45138 Essen, Germany
http://spunk.dnsalias.org (my server)
http://www.linuxaudiodev.org (Linux Audio Developers)
7588
days inactive
7589
days old
linux-audio-user@lists.linuxaudio.org
10 comments
6 participants
participants (6)
-
Anahata -
Chris Pickett -
Daniel James -
Joern Nettingsmeier -
Russell L. Harris -
Steve Harris