Speaker Cable Lengths

 

Bronze Member
Username: Myrantz

Post Number: 24
Registered: 02-2004
This may be a silly question, but with speaker level and distance settings are equal length speaker cables necessary for a/v receivers?

Cable lengths:
Front L & R are 12ft each
Center 6ft
rears 28 ft

As I need to run the cable for the rears along one wall I end up with about 12ft coiled up from the shortest distance rear. Is it necessary to maintain equal lengths? My reasoning tells yes but does anyone have different thoughts?
 

New member
Username: Airforceone

Post Number: 9
Registered: 02-2004
I thought you needed equal length wires but two different home theater installers told me it only matters with runs 50 feet or longer. Actually they disagreed and one said it took 75 feet for it to matter. I think he said something about the signal almost traveling at the speed of light and how hard it would be to detect one signal reaching the speaker before the other. Basically the difference would be almost impossible to measure, let alone hear. I've tried both ways and can't tell a difference.
 

Silver Member
Username: Geekboy

Post Number: 217
Registered: 12-2003
My Rantz: excellent point to bring up. I've generally been in the school of thought that the L/C/R trio should have equal cable lengths. (I have 12ga braided wire with an insulator ("ladder") in between the wire ($3/ft). My front array are each connected with 12ft of this wire.) I believe the rear affects (and rear surround), each as a pair, should have the same wire length as well... but not the same as the front array!

The whole thing on this is can you actually hear a difference? There has been many discussion about wire length and whether ALL WIRES in the system should be of equal length. I don't think so... especially in a discrete system. For the Stereo Pairs, I would try to keep them the same length (L/R, SR/RL, and RR/RL). Other than that... mine are not even the same gauge. :-) My rear speakers are about 14ga wire and didn't cost me $3/ft. :-)

Good point to argue about! I'm gonna go sit back in the corner and watch the fireworks from there.

Key:
L/R = Left/Right front speakers
C = Center front speaker
SL/SR = Left/Right surround speakers
RL/RR = Left/Right Rear Surround spakers
 

New member
Username: Airforceone

Post Number: 10
Registered: 02-2004
Let me put it this way, If two people have a flashlight and one stands 20 feet from a wall and one stands 50 feet from the same wall and they both switch on their flashlights at the same time, does one beam of light hit the wall sooner than the other? Well YES! But can you ever actually see this? NEVER. Even if one stood at 20 feet and the other at 100 it would still "appear" that the two beams of light hit the wall simultaneously.
 

Bronze Member
Username: Myrantz

Post Number: 25
Registered: 02-2004
Thanks for your views folks!

Actuall my rears are 38ft not 28 duh!- no matter! I didn't want to cut off the 12ft in case there was a difference @ $3.00 pm to replace again. But, at over 50ft to make any difference it may be safe to do so or it may be so irrelevent I'll just leave the coiled 12ft hidden behind the bookshelf which asks another question - does having a length coiled and tied create any probs although there's none that I notice - just interested for the sake of having things tweaked right.
 

Bronze Member
Username: Airforceone

Post Number: 12
Registered: 02-2004
Again, I've heard for some reason that coiling is bad. But then again that may have been for component video cables. When I wonder about stuff like this I just put in a DVD with effects coming from the speaker in question and make changes. Play something and while doing so play with the wire, like un-coil it, to see if you notice any difference in the sound when doing so. If not, your free to do what your doing. :-) If the sound suddenly opens up, then leave it un-coiled. I doubt you'll hear any difference.
 

Bronze Member
Username: Myrantz

Post Number: 26
Registered: 02-2004
AF1

Your dead right. I will do that and I agree - I doubt any difference but a little exercise will do me no harm! I've come to the conclusion that from reading all the tweaking hints that one thing does little but many combined makes a difference. The real fun comes from the looks and comments from the significent other!
 

Bronze Member
Username: Airforceone

Post Number: 14
Registered: 02-2004
Rantz,

The looks I get when doing this could burn through steel.:-) Let me know how it turns out.
 

Bronze Member
Username: Buckeyeshine

Post Number: 21
Registered: 02-2004
Actually from what I understand the shorter the length the more critical they are to be the same as a % of the difference is more imprtant. That is, if your fronts are connected and one is 5' and the other 10' that is 50% difference. On the other hand for rears where you may have 25', 30', 40'...lengths, 5 feet won't mean as much.

Now whether this is an old wive's tale and you would notice a difference with the human ear with current traveling so fast I don't know but this is what I have been told by some "experts" and seems somewhat logical. I would think the 2 fronts would be the most critical if this is correct.

Because the setup of my system puts one of my fronts right next to my receiver and the other 9' away is how I was told about this.

This concurs with what Audioquest's website says in their FAQ. They also say the Center does NOT have to be the same length as the fronts which contradicts what one of my local dealers told me.

According to Axiom's site the longer the run, the bigger the gage should be of the wire due to resistance. They say 12 gage is the most one should need for the longest of runs. This seems logical to me.

This was advice centered on the little benefits of very expensive speaker cables as the main concern with speaker wire is to not add resistance so gage was the most important consideration.
 

Bronze Member
Username: Petergalbraith

Post Number: 14
Registered: 02-2004
That is, if your fronts are connected and one is 5' and the other 10' that is 50% difference.

JDG,

I'm sorry but carrying that argument to extremes you'd hear a huge difference between a 1-foot run and a 10-foot run (a 1000% increase!). It makes no sense, electrically or otherwise.

I have kept my two main speakers at equal length but that's mainly because it pains me to cut that nice 10-gauge wire. What if I move stuff a bit and need that extra length later? But I think leaving it coiled stands a much bigger change of affecting the sound than cutting it to the needed length with no extra. I may decide to cut it!
 

Bronze Member
Username: Myrantz

Post Number: 27
Registered: 02-2004
Okay, I uncoiled the said '12ft' of coiled cable. I used the white noise test tone to determine any difference. Now, I don't know if it is 'the power of suggestion' but I believe I could detect a VERY slight increase of sound from that speaker. For a real test however, I'll get my wife to coil and uncoil the cable without telling me when while I listen with eyes shut. I'll let you all know if the result differs.

Ah - the things we do!

I think for the rears the cable is 16 guage, the fronts 10 and center 12. As far as different lengths are concerned (RE: Air Force One's torch theory) whether it be 50% or 1000%, would our ears pick the delay?

Another point is the age of our ears - a 20 yr old may detect a discernable difference from - er - let's say someone teetering around middle age!
 

Bronze Member
Username: Goose

Post Number: 55
Registered: 02-2004
Assuming that the signal travels at the speed of light, the delay caused by a difference of 1 foot of cable will be about 1 nanosecond (1 billionth of a second).
 

Bronze Member
Username: Goose

Post Number: 56
Registered: 02-2004
Just another number or two ... a 20kHz wave has a period of 50 microseconds. A delay of 1 ns is thus one 50-thousandth of a wave period (and corresponding smaller at lower frequencies). Even with a 50 ft cable length difference (50 ns delay), you would only get an error of one-thousandth of a wave period. This is what we scientists call Not Worth Worrying About.
 

Bronze Member
Username: Petergalbraith

Post Number: 21
Registered: 02-2004
I donet think the delay could be perceptible. I also thought equal lengths were requested to affect the sound in an equal way. Since I don't think any sufficiently large good quality wire could affect the sound anyway...
 

Bronze Member
Username: Myrantz

Post Number: 29
Registered: 02-2004
Peter

I'd say you're right on both counts but doesn't sub par cable affect the speakers impedence?

I looked up the following site (referred to by JDG) http://www.axiomaudio.com/archives/cable.html

Interesting! It suggests to use 12 guage for longer runs so I might change mine for the rears but only if can get 30m very cheap!
 

Bronze Member
Username: Buckeyeshine

Post Number: 25
Registered: 02-2004
Peter,
I believe I did qualify my staement questioning whether different lengths would be perceptible by the human ear.

I am certain the proper equipment could be connected to measure the difference between a signal passed through a 5' cable versus a 10' but I doubt the human ear could detect the differences.
 

Bronze Member
Username: Petergalbraith

Post Number: 24
Registered: 02-2004
My Rantz, actually I provided that link in support of not buying expensive cable. :-)
It's unlikely that even sub-par cable would affect impedance, but good quality cable doesn't necessarily mean expensive cable, right?
30 m does seem to be getting on the long side.

JDG, whenever I'm confronted with an argument I carry it to its extreme limit to see if it still holds. This tells me that if anything it would be absolute wire length that affects sound and not the ratio of the two wire lengths.

I think we all agree that using good quality 14 or 12 gauge cable is sufficient. I can get 14 gauge cable for around 10 cents a foot and 12 gauge for around 25 cents a foot (with lettering that says oxygen free and all that), so there's no way I'll be paying dollars per foot.

As for what to do with excess cable length (coiling vs cutting it off), it would be nice to find more info.
 

Bronze Member
Username: Myrantz

Post Number: 30
Registered: 02-2004
Peter

I do realise your link was about expensive cable being unnecessary. I wish I could purchase cable at the prices you quote - thus the 30m roll (best way to buy here) otherwise $3.75 pm. Our room is 8m long but requires 2 x 13 mts for rear wall mounts using equal lengths.
« Previous Thread Next Thread »



Main Forums

Today's Posts

Forum Help

Follow Us