[Captain Magenta]

I've noticed over the last year (since my obsession with headphones began)  that there are a lot of cans with single entry cables.  If the wire goes into the left cup then an extra length of wire must run through the headband to the right.  Does this not technically result in an (albeit miniscule) audio delay in the right cup? I know it may not be perceptable to the human ear but then why do a lot of higher end headphones eg. HD600 and all Grados have dual entry cables? 

 

[liamstrain]

Technically, yes. Practically, no - I do not think the difference over that extra 10 inches of cable, is even measurable. Much less audible. 
 
There are design and construction (and usability reasons) to choose single or double. I do not think absolute sound quality is a significant factor in that decision. 

 

[Lurkumaural]

Quote:

Technically, yes. Practically, no

Basically this.
 

 

[Captain Magenta]

Quote:

Technically, yes. Practically, no - I do not think the difference over that extra 10 inches of cable, is even measurable. Much less audible. 
 
There are design and construction (and usability reasons) to choose single or double. I do not think absolute sound quality is a significant factor in that decision. 

Yeah its just one of those things I've wondered about.  It's funny,  I've seen threads on A/V forums go on for dozens of pages debating this issue and many people insist on having their speaker cable exactly the same lengths.  Thing is that unless they are sitting exactly the same distance from each speaker then it is pointless as electrical current travels through wires many times faster than the speed of sound.
 

 

[liamstrain]

Penny wise, pound foolish.
 
For what it is worth, I recabled my Grados to single sided entry, and can detect no difference whatsoever sound wise between the originals, and the recable. They are, however, infinitely more user friendly.
 
Dual cable entry does allow you to make sure you have the same type of wire connecting both drivers. So that is nice. Sometimes the over headband wires are thinner, or going through a different metal (AKG 702 the frame bands are conductive and carry the signal to the right side, rather than using a threaded wire over). 
 
But overall, that is a non-issue as well. Just peace of mind for some people.

 

[Willakan]

Declaring that the difference in time delay would be audible is absolutely insane. 

 

[eugenius]

Luckily Ultrasone already uses a magenta flux capacitor that causes the signal to jump ahead 10 inches in time, thus reaching the other ear with no delay. Problem solved.

 

[Jaywalk3r]

many people insist on having their speaker cable exactly the same lengths.  Thing is that unless they are sitting exactly the same distance from each speaker then it is pointless as electrical current travels through wires many times faster than the speed of sound.

I've always made sure my speaker wires were the same length, not because of signal timing, but because the resistance of the wire varies directly with the length. If I want to use the same type of speaker wire, then the only way to have the same resistance is to use wires of the same length.

 

[liamstrain]

If you are comparing a 10 foot and a 20 foot run, that is 0.02 ohms in the 10 foot run and 0.04 ohms for the 20 foot. With an 8ohm speaker, that is a difference of .02db.
 
Just fwiw. Such low cable resistance (provided you are using a heavy enough cable for the lengths you need). Is unlikely to have an audible difference at common differences. 
 
See more fun math here.
http://www.trueaudio.com/post_008.htm

 

[jcx]

the order of magnitude between the speed of light and sound is a factor of a Million = 10^6
 
in cables EM fields propagate at 40-70% of c
 
so signal arrival time difference for any cable you can fit in your room is no problem
 
the resistance difference may not have much effect either
 
comments from Moulton's site:
 
...Then, a little later still, I got into some loudspeaker research, and found myself called upon one day to make a research recording, wherein I recorded a batch of clicks with very carefully documented changes in level between the stereo channels. This was one of those cases where I figured I knew what was going to happen before I started. Given my golden ears, there just wasn’t much doubt that I could hear the image move as soon as I tweaked the pan-pot even a little, so I decided to calibrate the changes to 1/10th of a decibel, so that I’d be able to really pick out the subtle differences in localization that were going to happen when the levels between channels changed. However, I was very startled to discover that the phantom image didn’t seem to move at all even when the levels between channels changed a whole decibel! I was so startled that I became positive I had made a mistake when preparing the tape! A little investigation (well, about three hours, including chasing down all the wiring in the monitoring system!) showed me that I hadn’t made a mistake, and when the dust finally settled I had found out something quite interesting: that as long as the difference between channels is less than 3 decibels, the phantom image hovers pretty much in the middle point between the two speakers. I promptly ran this down to my buddies at the local loudspeaker factory and we tried it in the anechoic chamber with blindfolds and people pointing at the imaginary phantom, and it still remained true: with up to 3 dB difference between channels (that’s half-power, remember!) the image didn’t move much, maybe five degrees. With between 3 and 6 decibels difference in levels, the phantom quickly and without much stability migrated to the louder speaker, hovering just inboard of that speaker, and once the difference was greater than 7 decibels, the phantom was for all intents and purposes coming from the louder speaker.
 

 

[Jaywalk3r]

If you are comparing a 10 foot and a 20 foot run, that is 0.02 ohms in the 10 foot run and 0.04 ohms for the 20 foot. With an 8ohm speaker, that is a difference of .02db.

Just fwiw. Such low cable resistance (provided you are using a heavy enough cable for the lengths you need). Is unlikely to have an audible difference at common differences. 

See more fun math here.
http://www.trueaudio.com/post_008.htm

Interesting point, though in the example to which you linked one lead was only 50% longer than the other, not 100% longer. I'd have to actually measure the resistance in one of the speaker wires to make a calculation of the actual effect. By just using the equation R = rho * L / A, it makes sense to not unnecessarily double resistance of one speaker wire compared to its counterpart when there is no marginal cost involved.

 

[khaos974]

Actually, the physics of speaker cables indicate that you should use wires as short as possible, regardless of asymmetry, the reason for this is to avoid the cables curling upon themselves.
 
(It should be noted that I said optimal, I made no implication concerning the audibility of the phenomenon.)

 

[Jaywalk3r]

It is important to avoid coiling speaker cable, but shorter is not always better. If using a short cable requires the cable to be run in close proximity to power cords, that is a Very Bad Thing™ in home audio. A longer cable run away from power cords is, in principle, much better. Ideally, speaker cable and interconnects should not run together, either.

Of course, it's usually difficult or impractical to set everything up optimally, so we take the strengths and weaknesses of the equipment and room design into consideration and do the best we can with it.

 

[leeperry]

Denon clearly claim in their D2/5/7K sales pitch that they do it to improve the SQ. I don't believe that the phase coherence would be tempered with....but this is open for debate I guess.
 
I already opened a thread on that matter a while ago: http://www.head-fi.org/t/417250/dual-entry-whats-the-point
 
And I personally HATE dual sided cables(it's so darn annoying to always have a cable hanging on your chest

), and I can't believe I would be the only one.

 

[Cakensaur]

i prefer cables on both sides. dont know why it just feels more stable and sctuff