big music in small spaces - how do I shield my audio cables from power cables RF signals

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Member Since: Nov 15, 2002

My recording booth/iso chamber is a closet. I have a remote computer station set up in there with everything I need on an A/B switch that ports my mouse, keyboard, and monitor into the closet. I have a nest of power and audio cords wound and jammed together, tucked indiscretely under the gap at the bottom of the door. The audio cables also happen to wind around the power strip and power supplies for my hardware components as well as an ancient monitor.
I've been noticing noice I can't identify. I'm thinking it's the power cables/supplies interfering with my audio signal on the way to the computer.
How can I shield my audio cables? Is there anything I can wrap around them to prevent this bleedthrough? Is there some kind of material I could partition them with? Space is an issue here, so I can't seperate the audio and power stuff unfortunately. Any suggestions?

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Contributor
Since: Sep 09, 2002


Nov 21, 2002 11:39 am

I bet aluminum foil would work. If it works for making radio antennas i bet it can shield again other EM. Its kinda what's inside some cables and inside of electric giutars to shield from outside RF interferance. on a similar note i'd like to shield the audio cables in my car. whatever we determine works for you, might work for me. -j

Member
Since: Nov 15, 2002


Nov 21, 2002 11:48 am

Ahhh... practical, cheap, and ugly as sin. Now that's my kind of solution! :) I'll try it this weekend, and if it makes a noticeable difference I'll let you know. Thanks for the advice!

Member
Since: Nov 15, 2002


Nov 21, 2002 11:51 am

Hey, does anyone know how far away from the source that the electromagnetic field from power cables/equipment would actually extend? Maybe I could run my audio out the gap at the top of the doorframe and my power coming in the below.

Administrator
Since: Apr 03, 2002


Nov 21, 2002 11:58 am

It is truly in everyone's best interest to take care when setting up a reocrding room to run audio cables nice and neatly parallel and power the same way. Preferably on opposite sides of the room...

Is sound like a pain in the butt, however it will not only save you noise and hastle but it will make your studio a heck of a lot neater...

Member
Since: Oct 31, 2002


Nov 21, 2002 12:05 pm

what the heck, i'll wrap all my cables in foil if it will help.

Member
Since: Nov 15, 2002


Nov 21, 2002 12:01 pm

...it matters whether they're parallel? Yer befuddling mah dumb cracker mind with that crazy mojo physics thing going on now. I knew I should've taken that class. :) I'm taking a vacation day tomorrow so I can record... Maybe I'll take a couple hours and see if I can re-route my cabling scheme. I'll pick up a box of foil on the home tonight.

<rubbing crystal ball> "I see... I see... much hammering... many cables stapled to a wall, holding cords which flow with arcane power... and a foil of the purest tin wrapped around them. Heed ye these words, that the moaning of ghosts in the machine may haunt your songs ne'ermore..."

Did a little search... found this on a website:
"Shielding the compartments of your hi-fi cabinet with copper screen or aluminum foil can protect components from RF fields."
It's from an article about reducing different kinds of noise, acoustic and rf. Here's the link:
www.chesky.com/articles/b...cle=technical13

Hey, thanks for the help guys!

Administrator
Since: Apr 03, 2002


Nov 21, 2002 12:19 pm

Ya it matters, you do not want your cables runing perpendicular (especially with power cables) If you cannot run your power and music cables seperately you are sometimes better running them side by side rather than crossing over each other at random.

There is radical scientific and cosmic explainations for this that I would rather not get into here, just do it! :-)

If you have a 20" cable that need to connect to something 2 feet away, wrap your extra cable in a neat little circle (like when you are packing them up for the road) and lay it out of the way, then it is running parallel with itself.

The fat one always watches us.
Member
Since: Nov 08, 2002


Nov 22, 2002 12:00 pm

i do a little work with networks- that said here's some basic rules:
1)you can't run communication cable parallel with power.
2)flourecent lights=min 8 inches away from unshielded cable (same as guitar cords)
3)any power cable, min=6 inches away
4)if possible, plug your music equipemnt on a seperate circuit from any monitor/tv/radio. even if thier turned off, if your cable tv cable is plugged in its using the ground from your tv-which is usally the same ground that your music stuff is using. getting an apc batt backup/power iso is the best. also unplug the phone thing from your modem, or the nic interface from cable modem. all those things pull crap noise from the outside world right into your song......

Chief Cook and Bottle Washer
Member
Since: May 10, 2002


Nov 24, 2002 12:05 am

Yow!

You've got a rough one! Personally prior to wraping half my house in tin foil, I would try hard to isolate the noise generator. I had one sound card that was picking up the cooling fan in my computer on the D/A playback circuit only. The noise was not present on recorded files. If it is truely a cord then try another cord. Try alternate routes for the cord. A different length of cord may work too. The length of the cord acts as an antenna and will pick up certain frequencies. Don't go exactly half or double the length of the problem cord. Use a cord that is not a direct multiple in length as a test substitute. If it is truely RF, you may have a big battle on your hands. I lived near an airport at one point and one of stereo's would pick up the radar pulse every time the dish came around. Never did get that worked out. Another trick is to kill all of the circuits in the house except the one your gear is on and see if that takes the noise out. Obviously if it does then turn each circuit back on and see which one creates the noise. Track back from that. If your house was wired in the 60's when they used aluminum wire....peace be with you! The copper connnections electricaly react with the aluminum and well...big mess.

Good Luck!

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