Karsoncookie Posted March 4, 2016 Share Posted March 4, 2016 I want to fish (an existing concealed joist 16" OC cavity) a number of different cables. The only question I have is- Will I end up with objectionable like induced hum/ noise etc? I'm an electrician, so I understand induction, but not in regards to low level audio. I have only ONE particular cavity I want to use They will run about 11' down the cavity, fished. So will be criss crossing or who knows what down there. Certainly in close proximity. Details- 2 - Romex,for 120VAC power. 1- Long Monitor cable to ocassionaly feed my TV input from my Desktop PC. 2 pair 14/2 basic Zipcord, feeding speakers (High sensitivy old school Klipsch) 1 pair Basic, regular (cheap) RCA cable feeding my old school receiver audio input from 1/8" out jack on my TV. In the real world, most people have a rats nest behind their TV, (probably none of you guys), and they don't have trouble. Or, maybe they do, and don't know better. I don't have the RCA yet. I need 20' total length. Maybe something with a heavier braid is better?? Probably not. Induction is induction. Or?? Thank you, Lars Quote Link to comment Share on other sites More sharing options...
Karsoncookie Posted March 4, 2016 Author Share Posted March 4, 2016 I should clarify - I WAS, but not for 20 yrs., an electrician. Didn't want to sound uppity. Lars Quote Link to comment Share on other sites More sharing options...
Coytee Posted March 4, 2016 Share Posted March 4, 2016 Could you run XLR cable and terminate it with RCA's (I presume) This by the way is more of a question than an attempted answer. I don't know if you'd need to run XLR connections to get the benefit of the XLR wire. I ran some Mogami Neglex. No hum here (though i am using XLR connections) http://www.mogamicable.com/category/bulk/microphone/quad/ Ordered it in a number of different colors. Made running it somewhat mindless and all I had to do was match the color (in the closet) with where they originated from. Otherwise, had I done all black, I would have had to tag each one or some other creative way of keeping track of which (of about 12 strands) was which. Quote Link to comment Share on other sites More sharing options...
Coytee Posted March 4, 2016 Share Posted March 4, 2016 I lied. I just counted. It was 18 strands Quote Link to comment Share on other sites More sharing options...
Matthews Posted March 4, 2016 Share Posted March 4, 2016 Morning Lars, My opinion, from a tube powered stand-point. You may or may not run into interference problems. When I was running strictly SS, it made little difference about power lines, interconnects and such running together. My system was dead quiet at idle. Running tube power, the story is a little different. I had to run a dedicated circuit along with its own dedicated ground. No power cables, interconnects or speaker cables are allowed to run parallel at any point. All interconnects run together in and out of one port and the power lines another. I added a Richard Gray conditioner as well. Any switching 12V devices such as my DAC power and phone charger are run on a completely different circuit. These are the biggest culprits of noise introduction. Keep them away from your power and interconnects! All of that being said, perhaps you can do a test run before actually fishing your cables? Tie everything together and power er' up. Check for any noise. If you have tube power or have plans to add it in the future, I advise to take necessary preparations now, it will save you a world of headache further down the road. Matt ♪ ♫ ♪ Quote Link to comment Share on other sites More sharing options...
efzauner Posted March 4, 2016 Share Posted March 4, 2016 Any way you can keep the audio cables and speaker cables on one side of the cavity away from the others? May I suggest you use high quality audio cables, once installed. they will be there for ever. 1/8 plugs are not that long lived, get cable so you can easily change connectors if needed. Also don't use simple zip cord. Use speaker wire that is intended for in wall installation. Quote Link to comment Share on other sites More sharing options...
Karsoncookie Posted March 4, 2016 Author Share Posted March 4, 2016 efzauner - I cannot keep them separated. Only way i could, is by drilling more holes in a finished floor, that would not be covered by furniture as my original hole placement is. Below this, is the type of crawlspace I used to go into as a kid, but ain't goin there no mo. So that won't work. I will think more about my cable selection. Thank you. Quote Link to comment Share on other sites More sharing options...
Karsoncookie Posted March 4, 2016 Author Share Posted March 4, 2016 Coytee - I wish you would have told me the day before you bought all those faceplates. I would have boughten shares in Leviton. Lars Quote Link to comment Share on other sites More sharing options...
muel Posted March 4, 2016 Share Posted March 4, 2016 I wouldn't want my audio cables running parallel with my power. Rule of thumb is 6" apart. The AC can induce voltage on nearby wires. Crossing at a right angle isn't so bad. For a 20' RCA I'd look at Blue Jeans cables... they have a shielded version of what you describe but I'd still want to keep it away from the AC. 1 Quote Link to comment Share on other sites More sharing options...
wvu80 Posted March 4, 2016 Share Posted March 4, 2016 I should clarify - I WAS, but not for 20 yrs., an electrician. Didn't want to sound uppity. Lars LOL! Nothing worse than an uppity electrician! I don't think most of us were alarmed, Lars. I feel pretty sure you are comfortable around cables. Quote Link to comment Share on other sites More sharing options...
Coytee Posted March 4, 2016 Share Posted March 4, 2016 Coytee - I wish you would have told me the day before you bought all those faceplates. I would have boughten shares in Leviton. I'll post a picture when I get home...but it's even worse than that. I had them custom made. I ordered them from (I forget) and they came pre-assembled. all I had to do was solider the wires and plug in. I have no memory of the cost but I'm guessing I have something near $750 just in the cover plates (and their mated hardware) I know it hurt when I got the bill....but... it's what I needed to clean it up. When I get home, I'll try to remember to post a picture of the wall with the wires hanging out before they were terminated. Talk about a rats nest!!! I did debate on just buying some pass through hole cover plates and plug directly into appropriate item....but.... my wife likes things neat & tidy. Quote Link to comment Share on other sites More sharing options...
Chris A Posted March 4, 2016 Share Posted March 4, 2016 I'd recommend twisting the pairs for common mode (60/120 Hz) hum rejection. Twisting can be done after the cable is pulled to achieve the number of twists/length of wire required. You can also get shielded wire (as you know) that : https://en.wikipedia.org/wiki/Twisted_pair Are you thinking about this for signal-level cable or loudspeaker (power) level? Chris Quote Link to comment Share on other sites More sharing options...
efzauner Posted March 6, 2016 Share Posted March 6, 2016 so induced noise is also proportional to how long they are coupled... so yes, you must bundle them together to put thru the hole, but then spread them apart! Also, most speaker wire intended for in wall is already twisted. Quote Link to comment Share on other sites More sharing options...
garyrc Posted March 6, 2016 Share Posted March 6, 2016 I wouldn't want my audio cables running parallel with my power. Rule of thumb is 6" apart. The AC can induce voltage on nearby wires. Crossing at a right angle isn't so bad. For a 20' RCA I'd look at Blue Jeans cables... they have a shielded version of what you describe but I'd still want to keep it away from the AC. Sound recording engineers used to cross their microphone cables at right angles (if they needed to cross at all). Quote Link to comment Share on other sites More sharing options...
Karsoncookie Posted March 6, 2016 Author Share Posted March 6, 2016 Chris- Both Speaker wire and RCA low level, and also 120vac power. Detailed in post #1.. Lars Quote Link to comment Share on other sites More sharing options...
Rivervalleymgb Posted March 6, 2016 Share Posted March 6, 2016 I don't like getting in crawl spaces much anymore, or in the attic. Still.... I drill through the seal plates at least 6" apart, more if I can. If I can I put power lines down one side of the cavity and speaker wires on the other side. Crossing is only done at right angles. You can always make low voltage connection wire out of cat6e; two pieces twisted together using a drill to make the length you need. I use colored wires to positive and white wires to negative.. Pain in the a** to do, but twisted pairs of twisted pairs does help with induced noise. Quote Link to comment Share on other sites More sharing options...
Karsoncookie Posted March 6, 2016 Author Share Posted March 6, 2016 Chris- Both Speaker wire and RCA low level, and also 120vac power. Detailed in post #1.. Lars Quote Link to comment Share on other sites More sharing options...
babadono Posted March 6, 2016 Share Posted March 6, 2016 Try to keep the 120 Vac away from the RCA and speaker wire like others have said. If you are connecting unbalanced equipment with the RCA connectors changing back and forth to XLR connectors will do nothing. The only thing that matters with interconnects of unbalanced equipment is the resistance of the shield. The lower the better. Quote Link to comment Share on other sites More sharing options...
japosey Posted March 8, 2016 Share Posted March 8, 2016 (edited) I agree with everyone for the most part. I try to avoid power wires too close to RCA and speaker wires. Sometimes you you can't avoid it and you have no issues. A lot of the modern, better quality amps, pre-amps and receivers do a really good job at filtering noise that may have been introduced prior to. Edited March 8, 2016 by japosey Quote Link to comment Share on other sites More sharing options...
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