Axiom Home Page Forums General Discussion Technical Questions Should speaker cable length be equal?

Kevin, what you were told frankly makes no sense. To the extent that greater "strain" would occur because of a lengthened wire(which is negligible at differences used in the home, as the table shows), it would occur if the shorter(e.g. 10 foot)wire was arbitrarily lengthened(e.g. to 40 feet)to satisfy some meaningless equal-length belief.

My 2cents,

I bought 3-spools of pheonix gold 12ga wire at about 1 dollar per foot. Here's how I cut up my wire since I might move it around in the future. I made 2-20 ft runs for the mains and 1-10ft run for the center. Then I used the remaining 2-50 runs for the surrounds. Now if I decide to move any of them I will have plenty of wire left over.

1 question I have is that I basically have the left over all piled up in coils like a garden hose in the back of my receiver. Will this cause any interference? I haven't noticed any noise or artifacts. But 1 responsed mention that coiling the leftover wasn't good.

Is it better to leave the leftover coiled cable behind the receiver or at each speaker? or does it matter? and if I shouldn't coil it up then whats the best way to reduce interference if I don't want to cut it up.

I was suprised this post was going on as long as it had, so I finally decided I had to check it out. I would say no, the length doesn't matter. You're using 12ga, and the signal is travelling so fast that it won't be an issue.

SimplyFun,

I, too, have heard that coiling the speaker wire anywhere is not a good idea. It supposedly increases the inductance of the wire. (An inductor, after all, is just a coil of wire.) I just don't know how much it increases the inductance.

I've also heard that whenever one cable crosses another, you should arrange it so that they are perpendicular, but that's a little extreme (kinda like keeping all your wires the same length.)

Did you also know that you should never let your wires touch the floor? Luckily, somone invented wonderful products like this to solve that problem...

SF, you're probably referring to Bren's warning about coiled speaker wire forming an inductor, and you're happy that now you have one more thing to worry about. Unshielded wire in a coil(I assume that you're speaking of part of the wire that's connected to the speakers)does in fact form an inductor and the resulting inductive reactance in the wire opposes the signal flow in direct proportion to frequency, i.e. higher frequencies are reduced proportionally more. This effect is used in speaker crossover networks when the inductor rolls off the high frequency response to prevent it from reaching the woofer. A little of the same effect can occur by simply tightly coiling excess speaker wire(the number and tightness of the coils are among the factors involved)and it's sometimes suggested to zigzag it rather than coil it. The loss of high frequency response from a few loose coils probably isn't audible, but good practice is to keep speaker leads short in general and uncoiled if there's more than is necessary for the run.

Then of course, for the ultimate in audiophile nirvana, you should buy at least a dozen of the cable supports shown in the link Peter provided.

OMG, you have to be kidding me on those speaker wire stands. They are 18 dollars a piece and I have 25 ft runs? I don't think so. They claim is, if there is something conductive in the floor this protects it. Well all the wire is on the floor, but on top of carpet with plywood under it so I'm sure it's not conductive.

Now this 12ga wire I'm using has thick plastic clear type insulation around it. I'm thinking the coiling I'm doing isn't affecting it. The problem is I don't want to cut the cables in case I want to move the speakers around so the length has to stay the same. I could try the zig zaging but would I really be able to tell a difference? I was thinking stacking the coiled wire on top of other speakers coils might cause some interference but I'm doubting that too.

How can you tell if inductance is occurring? Like I said it sounds fine no humming or noise that's audible. Is there some sort of test to prove whether or not this is a issue?

Thanks

I just found this excellent discussion about the effects of inductance on speaker wires.

Read the part that begins "Hu wrote" after the horizontal line. It's science/math-heavy, but pretty easy to follow and understand.

In reply to:

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SF, you're probably referring to Bren's warning about coiled speaker wire forming an inductor, and you're happy that now you have one more thing to worry about. Unshielded wire in a coil(I assume that you're speaking of part of the wire that's connected to the speakers)does in fact form an inductor and the resulting inductive reactance in the wire opposes the signal flow in direct proportion to frequency, i.e. higher frequencies are reduced proportionally more.

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Well, the Canadian Broadcasting Corporation (CBC Radio and Television) believes that coiled cable is enough of a problem that they have put into print that the practice is to be avoided - again, we're talking about a few feet of speaker wire in this case, but we're also discussing best practice - the original poster was concerned about lopsidedly loading an amp circuit and whether it would be better to just keep consistant wire lengths, my response was simply that I would personally rather use the shortest possibly cable (after all, he could have a wireless 802.11 transitter hack close at hand, and a HAM radio, and maybe a circa 1979 microwave).

Inductive coils are reality (as can be attested to by any mechanic that uses a scope - they're clipped over plug wire #1 and used to pick up engine timing - most now are some sort of fragile ferric material... or by anyone who has wound a coil around a locked off apartment cable box to steal cable signals - do NOT do this, especially if you live near an airport... the CRTC or FCC get really peeved when every time the radar sweep goes by, everyone in the building but you has their reception drop out!)

Again, will anyone notice the extra noise created in a coil of 5 ft of 12ga. stranded cable? Probably not... but why pay for 5 feet of cable that can only possibly degrade an audio signal?

Bren...

In reply to:

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I've also heard that whenever one cable crosses another, you should arrange it so that they are perpendicular, but that's a little extreme (kinda like keeping all your wires the same length.)

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Again, if we're talking best practice, the way they teach cable pullers for video assists and video camera to bale wire is in an S rather than a coil.

Bren...

Is it an S or an 8? I have a hard time picturing an S, but maybe I'm just dense.