Speaker wire lengths for HT

[mness4]

I ordered a bunch of speaker wire from Blue Jeans. While discussing the order, I mentioned that I was trying to keep a constant wire length for the fronts and center...similarly for the surrounds and rears. They told me that was a myth and that I could run only what was needed to get from A to B. I'm sure they know their stuff (not to mention that they could have sold much more cable otherwise). I was never sure if the phase delay would really matter, but I always tried to match just in case.

Is it true that this is a myth?

Mike

[Oblio]

If you do the math, the phase delay due to speaker wire length mismatches is magnitudes less than those due to the physical placement of the speakers themselves and the location of the drivers within each speaker.

[WMcD]

Yes it is a myth.

One way of looking at the issue is to compare the appoximate speed of light (186,000 miles per second) to the approximate speed of sound (0.2 miles per second). So the ratio is roughly 1 million to 1.

It is true that the speed of electical transmission in a wire is somewhat less than the speed of light. This depends on the size and spacing of the conductors and the nature of the insulation. It is less by what what is called the velocity factor. I'm guessing it 0.5 in speaker wire. It is fun to say, "Captain, we're down to 0.5 of lightspeed in this wire."

But sticking to the 1 million to 1 ratio: We see that if the left speaker is 1 inch closer to you than the right, we need a million inches of wire to make the same delay. By my calculations that is 16 miles of wire.

You can play with the math and ratios. But obviously a little difference in the length of wire means nothing compared to what is a very common offset of speakers. You can make a 1 inch difference just by turning your head.

Wm McD