Speaker Cable Length Differences: Do they matter?

[ryanosaur]

I couldn't bring myself to read through this whole thread... sorry. *blushes
I am reminded of the story of Rear Admiral Grace Hopper and a thing she was known for:

Grace Hopper is famous for her nanoseconds visual aid. People (such as generals and admirals) used to ask her why satellite communication took so long. She started handing out pieces of wire that were just under one foot long (11.8 inches (30 cm))—the distance that light travels in one nanosecond. She gave these pieces of wire the metonym "nanoseconds."[29] She was careful to tell her audience that the length of her nanoseconds was actually the maximum speed the signals would travel in a vacuum, and that signals would travel more slowly through the actual wires that were her teaching aids. Later she used the same pieces of wire to illustrate why computers had to be small to be fast. At many of her talks and visits, she handed out "nanoseconds" to everyone in the audience, contrasting them with a coil of wire 984 feet (300 meters) long,[39] representing a microsecond. Later, while giving these lectures while working for DEC, she passed out packets of pepper, calling the individual grains of ground pepper picoseconds.

(from wikipedia)

Thus I ask... if 11.8" is a nanosecond... and 11808" is a microsecond... and a microsecond is 1000th of a millisecond... (you see where I'm going with this?)...
I can't find a great quote, but we likely hear a latency of 2-3 milliseconds as two events. So lets get uber conservative and say that the speed a signal travels through that wire is only a FIFTH of what she claimed... so one microsecond might be only 2361" x 2000 for a conservative latency... that's 4.7 million inches of wire! we are talking about POTENTIALLY causing an audible latency.
Yes, this is a silly example, and my math may very well be wrong. But I will say I don't hear anything amiss with my cable lengths cut to size for each speaker run, as opposed to cut to equal lengths for all speaker runs. In fact I'd be willing to bet that a 25' run to your left speaker and a 5' run to your right speaker will sound no different.

Anybody wanna set up a DBT and give this a spin? I'll bring 60" of wire. You bring the 4.7 million inches!

By the way... does Roger Russell tell us what guage we need for a run that long?

 

[Speedskater]

We still have one of those Admiral Grace Hopper nanosecond's up in the attic. It was a handout at a lecture.

 

[HTfreak2004]

Upon connection to my receiver and speakers, it seems the speaker wire is too thick to fit in the tiny hole at the back of my speakers.

Any clue?

Try WD-40 she’ll work every time no exceptions

 

[Edgar Betancourt]

I agree in general it doesnt matter however you don't want to want a leg 4 times longer than the other!

 

[lovinthehd]

I agree in general it doesnt matter however you don't want to want a leg 4 times longer than the other!

Why, what difference would that make?

 

[Edgar Betancourt]

Why, what difference would that make?

Though small in an absolute sense a cable 4 times longer than the other creates an impedance mismatch to the amp given that one cable has 4 times the resistance of the other. The object is to keep them as close to each other as possible.

 

[lovinthehd]

Though small in an absolute sense a cable 4 times longer than the other creates an impedance mismatch to the amp given that one cable has 4 times the resistance of the other. The object is to keep them as close to each other as possible.

It's an extremely small difference and not worth worrying about (as long of course as its of proper gauge for the length and impedance at the longer length).

 

[Edgar Betancourt]

Precisely if using 16 guage wire, which everyone seems to think is good enough, you will most definitely have a significant difference

 

[lovinthehd]

Precisely if using 16 guage wire, which everyone seems to think is good enough, you will most definitely have a significant difference

Depends on the distance needed. If someone doesn't ascertain their needs properly, that's another matter. I don't know that 16g is what "everyone seems to think is good enough" comes from anywhere but your butt.

 

[keith_h]

Good discussion. I'm in the 16G camp. I've got speakers on the wall with the maybe 5 metres per side of 16G in the wall connected to sockets on the wall jumpered to the amp itself with leads terminated with banana plugs.

Amp has 100W nCore modules + Dirac, sounds epic. Every now and then I get the urge to upgrade the wire to 12G but then I ask, will it really make a difference? I am yet to be convinced it might be worth the effort.

 

[lovinthehd]

Try this wire table for impedance/length/gauge. http://roger-russell.com/wire/wire.htm#wiretable (great site for things speaker cable in general)

 

[highfigh]

I agree in general it doesnt matter however you don't want to want a leg 4 times longer than the other!

And yet, that's exactly what exists in many thousands of equipment installations. What should be done with the excess on the short runs- coil it up and hide it in a wall or in the rack? Near power cables? That's a big NOPE. Try telling someone you need to use equal lengths for each speaker and show them the additional cost on the invoice- I suspect you'll enjoy that particular experience so much that you won't want to re-live it.

 

[highfigh]

Good discussion. I'm in the 16G camp. I've got speakers on the wall with the maybe 5 metres per side of 16G in the wall connected to sockets on the wall jumpered to the amp itself with leads terminated with banana plugs.

Amp has 100W nCore modules + Dirac, sounds epic. Every now and then I get the urge to upgrade the wire to 12G but then I ask, will it really make a difference? I am yet to be convinced it might be worth the effort.

So, you added two connection points at every plug and wall plate on each wire. If you never disconnect the equipment, those plugs and plates don't do anything unless they're visible to everyone and even then, they don't help performance.

 

[Jerkface]

I can't find a great quote, but we likely hear a latency of 2-3 milliseconds as two events.

I'd dispute this. 2-3 ms latency is well below the threshold at which 99% of musicians can detect timing issues. 5ms is usually good enough to keep everyone in time. 10ms, now you're into territory where people are hearing something happen later than they're PLAYING it. This is digital audio recording fundamentals stuff, and I know it from experience.

I doubt seriously that your ear, without a tactile feedback to aid it, could detect 3ms latency.

 

[Otto Pylot]

Try this wire table for impedance/length/gauge. http://roger-russell.com/wire/wire.htm#wiretable (great site for things speaker cable in general)

That is an excellent guide and one that I've used a couple of times to determine maximum length and wire gauge based on the ohm rating that I wanted to push.

 

[lovinthehd]

I'd dispute this. 2-3 ms latency is well below the threshold at which 99% of musicians can detect timing issues. 5ms is usually good enough to keep everyone in time. 10ms, now you're into territory where people are hearing something happen later than they're PLAYING it. This is digital audio recording fundamentals stuff, and I know it from experience.

I doubt seriously that your ear, without a tactile feedback to aid it, could detect 3ms latency.

Yeah that's like moving your speaker a small bit at almost 1 ms per foot, so am imagining it would be really hard to tell the delay difference in a speaker moved 3 feet in either direction....

 

[Richard N. Marsh]

View attachment 14226

More often than not, I see the common question pop up in our forums regarding speaker cable length differences between two or more speakers.

Folks often wonder if the cable length between the main front channels need to be identical or close to identical.

They are often misinformed by exotic cable vendors or cable forum cult hobbyists that cable lengths need to be kept identical to avoid amplitude or phase/time delay differences between the two. Some even imply speaker cables exhibit transmission line behavior.

Does it really matter, do these claims have any merit?

[Read the Speaker Cable Length Article]

 

[Richard N. Marsh]

View attachment 14226

More often than not, I see the common question pop up in our forums regarding speaker cable length differences between two or more speakers.

Folks often wonder if the cable length between the main front channels need to be identical or close to identical.

They are often misinformed by exotic cable vendors or cable forum cult hobbyists that cable lengths need to be kept identical to avoid amplitude or phase/time delay differences between the two. Some even imply speaker cables exhibit transmission line behavior.

Does it really matter, do these claims have any merit?

[Read the Speaker Cable Length Article]

 

[Richard N. Marsh]

the Zo of of the amp is not alone. You have to add the Rs of the speaker cable.




red is distortion from driver counter emf with 12 ft of #12 awg and with real speaker for load







here is with 1 foot of spkr wire.







back to 12 feet but sense lines carefully added.



Note that this is with a small 6.5 inch driver and only 5W into it. Distortion goes up with power applied and also with larger multiple bass/mid drivers. Like a floor standing unit could have. Instead of 0.5% it goes up to 5% plus. It is best to place the power amp as close to the speakers as possible.

Thx-RNMarsh

 

[gene]

the Zo of of the amp is not alone. You have to add the Rs of the speaker cable.



red is distortion from driver counter emf with 12 ft of #12 awg and with real speaker for load





here is with 1 foot of spkr wire.





back to 12 feet but sense lines carefully added.



Note that this is with a small 6.5 inch driver and only 5W into it. Distortion goes up with power applied and also with larger multiple bass/mid drivers. Like a floor standing unit could have. Instead of 0.5% it goes up to 5% plus. It is best to place the power amp as close to the speakers as possible.

Thx-RNMarsh

I always factor in Rs, Ls and Cp of speaker cables when doing analysis. There is something amiss with your distortion plots. I actually measured speaker cables impacts on real amplifiers with real speakers and the results were pretty nill.

See 12:03