Speaker Cable - Q. Should I use a dedicated bi-wire cable or two single cables when bi-wiring my loudspeakers?
The capacitance and inductance of a speaker cable depends on the separation of the two conductors. The nearer you place the two conductors together the higher the capacitance and the further away you place them from each other the higher the inductance and vice versa. It is therefore important to control the geometry of the cable along its entire length. By using two separate runs of single wire cable in a bi-wire set up you lose this control because the two runs inevitably lie in different configurations between channels and also vary in distance from one another within each channel. The only way to make sure that both sides will have the same inductance and capacitance is to use a dedicated bi-wire cable with a fixed geometry. Our testing with multi tone signals showed that intermodulation distortion is reduced when using a bi-wire configuration, but that this effect was lessened when the two cable runs were not of identical construction. By the same token, this factor was not so important when bi-amping and no real difference could be measured when using separate cables of different types with separate amplifiers either in vertical or horizontal mode. As long as the two runs of the same cable were of exactly the same length and could be bound together in some way you would probably get good results, but not quite as good as using the dedicated bi-wire version of that same cable.