Axiom Home Page
Posted By: seank Should speaker cable length be equal? - 12/06/03 08:02 PM
I just received my Axioms (M22tis, VP150, QS8s) and my HT receiver (Harman Kardon AVR630). I am waiting for my HSU STF-2 sub to ship.

I have a long length of 12 gauge speaker wire and I am ready to cut into segments and set everything up. My question is does it matter if each speaker has a different length speaker wire?

Is there any reason to make sure speakers have the same length? If so, does that apply to all speakers, including surrounds, or just mains and center?

I know that in theory they should be same length, but if they are all under, say, 50 feet does it really matter?

Thanks for any advice. I am a total newbie to home theaters and I am doing my best to learn as I go.

-Sean
Posted By: DJ_Stunna Re: Should speaker cable length be equal? - 12/06/03 08:18 PM
I doubt it matters, especially because you have 12 AWG cable...

That being said, I always make sure the lengths are equal - yes, I'm paranoid.
Do you mean if the wire to your surrounds is 45 feet then you also make the wire to your center 45 feet?

or do you mean that the two fronts are of equal length and the two surrounds are different length but equal to each other

did that make sense?

Am I wrong in thinking that the differences in length would have to be enormous before they made an audible difference?


Posted By: Haoleb Re: Should speaker cable length be equal? - 12/06/03 09:41 PM
I dont wanna sound like i know what im talking about when i dont for sure. but i remember reading somewhere that generally its a good idea to keep them the same when possible. not so much as keeping the center the same lenth as the rears. obviosly not. you want the shortest possible. but if it means making one of the front speakers 10 feet long and the other 15 id probbly make em both 15.
Posted By: willscary Re: Should speaker cable length be equal? - 12/06/03 09:55 PM
Keep them as short as possible to prevent loss. Bigger cable helps more than anything else. People who claim the longer path causes delay or response variations are peddling snake oil. While it is true that if using 22ga cable and having one cable 4 feet and the other cable 150 feet long will show a very audible difference, there will not be an audible difference if one 12 ga cable is 15 feet and the other is 25 feet.

Posted By: seank Re: Should speaker cable length be equal? - 12/06/03 10:10 PM
Let me use some harder numnbers. Lets assume the distances to my left front, center and right front are 25 feet 30 feet and 35 feet, respectively.

Should I cut them each to the minimum that they need, or should I make them all 35 feet?

Then for the surrounds, because I have to go around door frames, etc., I need one to be only 10 feet and the other to be 40 feet.

Should I make all 5 wires 40 feet? If not should I make the two surrounds 40 feet? Or should I cut them all to the length that is needed.

I am tempted to make the front speakers all 35 feet, but to cut the surrounds to 10 and 40 feet. This is mostly because I just barely have enough wire right now to do this. Plus I don't know what I would do with the extra wire going to one of the surrounds if it is 30 feet too long.

As a side question, is there any problem with running several sets of speaker wire along side of each other (so that they are touching) for part of the run?

Once again, thanks for all the help!

-Sean
Posted By: willscary Re: Should speaker cable length be equal? - 12/06/03 10:15 PM
Use 12ga cable. You have no problem running them side by side. Hell, they come out of your amp close together. If you biwire, you would run them together. There is no problem. Use the shortest lengths you can to minimize loss. Even the surrounds, with 1 being 10ft and the other being 40ft will not be a problem as long as you use a 12ga cable. If you are really worried, go to a 10ga or an 8ga cable (providing you can get banana plugs or spade lugs to fit them) and then there will definitely not be a problem.
Posted By: Ken.C Re: Should speaker cable length be equal? - 12/07/03 12:26 AM
Let's talk lightspeed, or something near it. Not to mention the speed of sound. Don't worry about it. It would take tremendous differences to make a difference. I am sure JohnK will cite an article about the subject...
Posted By: chesseroo Re: Should speaker cable length be equal? - 12/07/03 12:41 AM
In reply to:

I have a long length of 12 gauge speaker wire and I am ready to cut into segments and set everything up. My question is does it matter if each speaker has a different length speaker wire?



No, the wire lengths will not make any difference.
It is human perception and paranoia/misconceptions that may believe it will.
You could be using 16ga for distances under 50 feet and you still would not have an audible difference.
I think many have absolutely no notion of the speed of electricity.

Search backwards several months and you will see this topic has been covered quite heavily.

On another note, you may want to cut the pieces a bit longer than you originally calculated just in case in the future you decide to move the speakers a couple of feet in any particular direction.
Posted By: willscary Re: Should speaker cable length be equal? - 12/07/03 12:49 AM
I agree that the speed of electricity is too great to influence the flow between a long and short cable. However, I stand by my statement that a noticeable difference will occur between a 4 foot cable and a 50 foot cable if the cable is 22ga. the smaller the wire, the greater the loss. A few db loss on a long run with a tiny cable is most definitely audible. Use 12ga cable or larger and there will be no problems at 40 or 50 feet.
Posted By: chesseroo Re: Should speaker cable length be equal? - 12/07/03 01:14 AM
Since the original poster told us his cable was 12ga, there was never an argument about longer distances and lesser gauges.
However, with the distances he had specified, he would not get any signal loss even while using 16ga cable which was my point.
Obviously 22ga at 40 feet is a bit silly but so is using 10 or 8ga wire.

JohnK had posted on this not long ago. He linked to a webpage with the table of recommendations (based on science) enclosed. It is very useful for obtaining a general idea of max lengths per gauge and he does discuss lengths beyond 50 feet.
Posted By: willscary Re: Should speaker cable length be equal? - 12/07/03 02:10 AM
"Obviously 22ga at 40 feet is a bit silly but so is using 10 or 8ga wire."

If I could find some good, reasonably priced in-wall 8ga wire I would most definitely install it. Who knows what future upgrades may be, and who knows what the impedences of those speakers may be. Just looking at the length of run and the wire size works in most cases, but a speaker that is rated as 4 ohms may actually dip into the 2 ohm range at certain bass frequencies, and such a speaker connected to an amp by a 40' cable would definitely perform better with 10ga wire than 12ga wire.
Posted By: Ken.C Re: Should speaker cable length be equal? - 12/07/03 03:58 AM
I've got some 8 ga in my car that was relatively inexpensive (something like $30 for 8 feet or so).

Of course, it's my jumper cables...
Posted By: JohnK Re: Should speaker cable length be equal? - 12/07/03 04:16 AM
Sean, I'm aware of two claimed disadvantages of unequal length speaker wires. The first, more commonly raised, that there will arise a "timing" difference between the speakers, is total nonsense. Speaker wires carry the signal at speeds approaching that of light(close to 186,000 miles per second). The differences in length that could possibly exist in the home result in far less than a millionth of a second delay and are meaningless.

The second complaint is that the greater loss due to more resistance in the longer wire will "unbalance" the sound. This would be theoretically possible, but doesn't happen with the gauges and lengths of run used in the home. As the handy table at the end of this article shows, even the difference in loss on your 10foot/40foot combination would only be about 0.1 dB(out of maybe a 70-80dB average sound level). Moving your head a couple inches or putting a pillow on one side could have more effect.

Of course, as Bill and others have mentioned, for a totally different reason very thin wire shouldn't be used on long runs(e.g. 24ga on your 40 foot run).The table here shows recommended usages to avoid having a too-high resistance interract with the swings in speaker impedance and cause fluctuations in frequency response.

So, the differences in length which you propose would cause no problem, and in addition the 12ga wire would be more than enough for even your 40 foot run.
Posted By: seank Re: Should speaker cable length be equal? - 12/07/03 04:58 PM
Thank you everyone for your responses. You confirmed what I had thought, but I justed wanted to make sure there weren't issues I wasn't aware of.

-Sean
Posted By: BrenR Re: Should speaker cable length be equal? - 12/11/03 02:36 AM
Long time skulker, first time poster...

At the distances for cable ga. you describe, it's really academic matching lengths, I'd save the few dollars and make them as short as reasonable for your setup.

Bren R.
Posted By: mwc Re: Should speaker cable length be equal? - 12/11/03 05:18 AM
Welcome! and skulk no more. Join the fray.
Posted By: BrenR Re: Welcome - 12/11/03 06:17 AM
Thanks for the welcome - figured I'd finally sign up for a username and post.

Bren R.
Posted By: KCSkins Re: Should speaker cable length be equal? - 12/11/03 06:56 PM
I agree with everything JohnK has said in his previous post. However, I would like to add what I was told about speaker cable lengths when I first got into hifi quite some years ago.

In regards to a two-channel setup, I was told that it is very good practice to make sure that your speaker cables are of equal lengths and to keep them as short as needed for your space. This is because of the resistance and strain placed on your amp to carry the current to the speakers. Your amp is forced to work overtime on one channel if that specific cable is significantly longer than the other one. After a while, it could be the cause of failure on the amp. Please noticed that I said "significiantly longer." I'm sure that a relatively slight difference in variation is fine, and that the cables don't need to match down to the exact centimeter.

With that in mind, for my five-channel setup, I've got the front l/r speaker cables the same length (about 6' each), the l/r rears the same length as each other (about 15' each) and then a short run of 4' to the center channel.

Hope this helps.
Kevin
Posted By: BrenR Re: Should speaker cable length be equal? - 12/11/03 10:33 PM
In reply to:

In regards to a two-channel setup, I was told that it is very good practice to make sure that your speaker cables are of equal lengths and to keep them as short as needed for your space. This is because of the resistance and strain placed on your amp to carry the current to the speakers. Your amp is forced to work overtime on one channel if that specific cable is significantly longer than the other one.



Again, I'd say it's mainly academic at that point, the extra strain on the amp from 10 feet more 12ga. wire is negligible. What would be worse would be the inductive coil created by having extra wire hanging around, which would somehow find its way into a looped pile, most probably through a well meaning significant other.

Bren R.
Posted By: JohnK Re: Should speaker cable length be equal? - 12/11/03 11:07 PM
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.
Posted By: SimplyFun Re: Should speaker cable length be equal? - 12/12/03 02:30 AM
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.
Posted By: Zarak Re: Should speaker cable length be equal? - 12/12/03 02:34 AM
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.
Posted By: pmbuko Re: Should speaker cable length be equal? - 12/12/03 04:17 AM
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...
Posted By: JohnK Re: Should speaker cable length be equal? - 12/12/03 06:07 AM
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.
Posted By: SimplyFun Re: Should speaker cable length be equal? - 12/15/03 01:15 AM
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
Posted By: pmbuko Re: Should speaker cable length be equal? - 12/15/03 01:34 AM
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.
Posted By: BrenR Re: Should speaker cable length be equal? - 12/15/03 03:46 AM
In reply to:

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.



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...
Posted By: BrenR Re: Should speaker cable length be equal? - 12/15/03 03:49 AM
In reply to:

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.)



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...
Posted By: Ken.C Re: Should speaker cable length be equal? - 12/15/03 05:24 AM
Is it an S or an 8? I have a hard time picturing an S, but maybe I'm just dense.
Posted By: pamorin Re: Should speaker cable length be equal? - 12/15/03 07:53 PM
Speed of sound 340 meters per second.
Speed of light 300,000,000 meters per second.
one million time faster.
If electricity is ten times slower than light, it is still 100,000 faster. So by the time the current has done 50 meters (150 feets), the sound has done 0.5 millimiter (one fifth of an inch).
THere may be other parameter like resistance of the wire and electrical properties but on speed, nobody can hear the difference on speed only.
Posted By: pmbuko Re: Should speaker cable length be equal? - 12/15/03 08:06 PM
Welcome to the forum, pamorin! Thanks for the numbers.
Posted By: KCSkins Re: Should speaker cable length be equal? - 12/15/03 11:10 PM
"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."

Sorry, John, but I'm not making sense of what you're saying here, either. Please explain it further. Are you saying that to match the shorter wire (10' in your example) to the longer one (40') you'd somehow stretch the shorter one out another 30'? Or are you saying that you'd attach another 30' of wire onto the 10' wire so that the left and right wires would now each match 40'? If either one of those descriptions is correct in what you're saying, then you've misread my original point.

As far as the belief being meaningless, I'm sharing what the audiophile who got me started in this hobby shared with me so many years ago, which is that it's good practice to have your left and right speaker cables of equal lenght (or as close as possibly, anyway). By all means, go ahead and run your speakers with two cables of vastly different lenghts. I personally choose not to do it which is why I suggested not doing it here in regards to the original post.
Posted By: pmbuko Re: Should speaker cable length be equal? - 12/16/03 01:03 AM
KC,

I was a little confused when I first read JohnK's post, too, but I can explain what he was trying to say.

In all cases, it is better to have a shorter wire than a longer wire, since a shorter wire will present the amp with a lesser load. The benefits of short wire far outweigh the benefits of matching wire lengths. For this reason, having unequal wire lengths is much better than matching lengths to the longest required length.

I think that's clearer.
Posted By: BrenR Re: Should speaker cable length be equal? - 12/16/03 01:25 AM
In reply to:

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



An S (ESS)... much like I think it was JohnK mentioned about a zig-zag... take the area behind your entertainment stand... rather than coiling it, a better idea (though you still won't notice a difference I'm sure) would be to snake it in an S pattern... like swishing when skiing. Draw a wavy line on a piece of paper and stick it to the bottom of my message (and save me from drawing some terrible ASCII drawing!) *laughs*

Again, it won't make a shred of audible difference to your speaker cables, but if you make a career move into broadcast later in life, it's something to remember... or something to notice if you're ever at a live televised event, you'll notice a good cable puller will have a minimum amount of cable lightly looped and separated over his arm and the rest of his slack will be snaked rather than coiled behind him.

Like most things HT-related, this shouldn't keep you up at night.

Bren R.
Posted By: Ken.C Re: Should speaker cable length be equal? - 12/16/03 04:48 AM
OK. An extended series of Ses. I couldn't figure out how to make just one S out of a bunch of cable...
Posted By: JohnK Re: Should speaker cable length be equal? - 12/16/03 07:17 AM
Yes, Kevin, that's exactly why what you were told makes no sense. Sean would arbitrarily have to use a 40' wire on the 10' distance to his closer surround in order to satisfy the, again meaningless for home distances, equal-length requirement. That's what would cause an(insignificant)additional strain on the amp. If the distances in question are significantly unequal, e.g. the 10'/40' here, it's obviously impossible to both have the lengths equal and at the same time no longer than needed.
Posted By: KCSkins Re: Should speaker cable length be equal? - 12/16/03 06:45 PM
John- that's why I originally made my statement in regards to a two-channel setup. I think there was some miscommunication here, so no big deal. Moving on.

pmbuko- thanks for helping clear that up for me, too.
Posted By: BrenR PMBuko - Should speaker cable length be equal? - 12/17/03 12:52 AM
In reply to:

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...




http://www.audiotweaks.com/reviews/cblelevators/page01.htm - somebody apparently disagrees with our laughing at these speaker wire stands, then again, it IS a link to a site that suggests packing a receiver in play sand to minimize sympathetic vibrations.

Bren R.
I thought everyone uses the play sand .
play sand?! BAH! I only use pure, polished silica. Coincidentally, the stuff also sells as cat litter.
Some of these ppl are downright delusional.
Sympathetic vibrations eh?
I feel sympathy for someone alrighty and its that poor delusional sucker he thinks he needs those pieces of junk.
The next tweak will probably be flicking the lights on and off. Has something to do with excitation of electron flow in the walls.
© Axiom Message Boards