Jumpers vs bi-wire

Flickkit, it doesn't quite work that way. The point of bi-wiring is to have the currents that flow through the high-frequency drivers travelling in a different wire than the currents for the low frequency drivers. If it was wired as you suggest it would be no different that single wiring with a jumper. Both high and low frequency currents would flow in the same piece of wire. Jon Risch at audioasylum has some good material on the subject.

But Nighthawk, the signals going to the separate points on the speaker are identical (there is no separating going on at the amplifier end), so bi-wiring is exactly like Flickkit said. Doubling the size of a single wire will give you the same effect as by-wiring, with less fuss.

Inpep, nope it's not the same. The gauge of the wire is irrelevant. The high frequency currents are much less in magitude than the low frequency currents. Assume the amp is an ideal voltage source. It's output is no different whether you bi-wire or not. The low frequency currents will cause a certain amount of voltage drop in the wire. The high freq currents will cause much less. If you combine them in the same wire, the low freq signals will modulate the high freq signals. If they are in different wires, they won't. See Jon Risch's tutorial at the link below.

http://www.geocities.com/jonrisch/biwiring.htm

Nighthawk, that is true if the wires see different frequency content, which is true if the speaker is bi-amped with the crossover before the amplifier. In this case, both wires have as their source the same frequency content since the dividing network is at the speaker, not at the amplifier. The low frequency driver gets the whole signal and the high frequency driver(s) also gets the whole signal, but then passes through the crossover to eliminate the low frequencies. Just adding a wire that goes to the "high frequency" terminals on the speaker doesn't render the feed intelligent so that it knows which wire to follow!

BTW, all waves modulate each other to give the final waveform, which is the sum of all of the modulations.

Inpep, with a speaker designed for bi-wiring, the crossover network doesn't bridge the high and low speaker terminals. Yes, they do see the same frequency content. However, the high-pass filter network goes to the tweeter (and maybe mids) while the low pass filter network goes to the woofer (and maybe mids). It is as if there were two independent speakers in the same box - one for highs and one for lows. This is why you need jumpers if you're not going to use the bi-wiring capability. That's the only way both filter networks will be connected to the signal.

The high speaker terminals in a bi-wire setup don't see the IxR losses due to the large woofer currents passing through the wire. (Tweeter currents are comparatively tiny.) The woofer currents are confined to the low wire. It is the same as bi-amping in this respect. Thus the high wire is free from this admittedly small amount of distortion due to the passive losses of the wire. This assumes the amp is a good enough voltage source that it is not affected by the back EMF from the woofer which would then modulate both wires anyway. The wires are not ideal - they have resistance, capacitance, and inductance. You have to consider these properties to understand why bi-wiring works.

As to the audibility of bi-wiring, who knows? I think the effect is fairly small. It would seem that the shorter the cable, and the heavier the gauge, the less difference it would make, assuming the same cable make and model was used in both single and bi-wired configurations. I'll take a better single-wired cable over a lower performing bi-wired cable anyday.