will different lengths affect sound

No!

I have not met anyone with speaker cables longer than (20Hz to 20kHz) 1500 meters, let alone 150,000 meters.

Maxwell and Kelvin says, for simplicity sake, and I quote ..."the length of the wire is important when the signal includes frequency components with corresponding wavelengths comparable to or less than the length of the wire.".... (i.e. Transmission Line Analysis)

But here in Audiogon, everything is possible he,he,he....or should I say there are people here with excemplary hearing abilities! Enjoy your un-common gifts he,he,he!

It will only affect $value if it's not cheap bulk wire.

It depends what jeans you have on. (sorry, that old post still makes me smile)

Much simpler explanation than transmission line analysis:

Inductance of straight wire runs in order of 400nH/ft. Inductive reactance of 10' of speaker wire (20' counting both ways) at 20kHz is Xl=2*pi*20e3*20*400e-9=1ohm.
Difference between 10' and 100' of speaker cable at 20kHz is
9 ohms. You can argue that tweeter has higher impedance at 20kHz but often there is also compensating network of capacitor and resistor across the tweeter to even it out. Let assume that we care only about 10kHz range - the difference is still 4.5 ohm. It is not even an issue of signal divider but phase shift. 4 ohm of inductive reactance with 4 ohm of resistive load would shift phase by 54deg.

Let's assume 10' and 20' cables. At 10kHz difference of reactance between them would be 1 ohm while difference of phase shift with 4 ohm resistive load would be about 3 degree. I'm not sure what kind of load different speakers present at 10kHz but all I'm saying - it might be audible.

That's right. If you wear waxed Dior - everything is possible.