biwire trick

If the wires are the same type and close to the same length and are all grounded together at the binding post on the amplifier end then this cannot possibly make any difference at all - unless you fixed a poor contact when making the change or unless you concentrated harder than usual trying to discern a change (in which case most people do hear a change or think they do - due to the placebo effect)

Al,

I think the spacing between the wires would need to be significant to be audible. If the wires were 1 meter apart (huge) then I calculate a roll off at 20 Khz of 0.25 dB into an 8 Ohm load (most tweeters) compared to the signal level at 200 Hz. This is peanuts and barely at the threshold of audibility.

Fortunately, someone has already worked it out for any configuration and the details are here

If the biwires are in the same jacket or are laid out within an inch of each other (most likely scenario) then my original statement stands.

However, not knowing what crazy setups people might dream up and use, I guess I stand corrected.

Al,

The majority of tweeters are above 6 to 8 Ohms in the 10 KHz to 20 Khz range - rising with frequency due to the inductance. So the applet formula in the link is a pretty good approximation for the 10 KHz to 20 KHz range.

I think we can all agree that below 10 KHz we can pretty much ignore the effects of cable inductance.

In the applet I used 5 meters of speaker cable with + and - leads separated by 1 meter in order to get a 0.25 dB drop at 20 KHz compared to 200 Hz. I deliberately used an "extreme example" to show that the effect is very small in all situations.

However, the effect does exist and you are absolutely right that it might be audible in some situations. I stand corrected.

I would argue that this "trick" is definitely the wrong way to bi-wire speakers - at the very least it goes against normal way to make electrical connections which is in general to use either two wires side by side in close proximity for low frequencies (audio) or a coaxial cable for ultra HF applications.

Wrong? Different.

No just plain wrong. If one wanted to roll off the treble ever so slightly then there are better tools for that, such as tone controls, an EQ or more room treatments etc.

Cables should be neutral. Using cables to tune things is such a cumbersome way to achieve a simple task it beggars belief!

Tvad is absolutely right about education - knowledge certainly does instill principles about the right way and wrong way to hook up electronic equipment.

All I am saying is that from a "best practice" perspective it is wrong to use speakers wires with a large + and - wire separation to create excessive induction in a part of the system circuitry that is supposed to be as transparent and loss-less as possible.

Of course you are all free to do whatever you want. If an odd way to hook things up happens to work and you like to do it then great - it is not wrong from your individual perspective with your system as it just happens to sound better.

However, on the whole across all the many systems world wide, your approach is not best practice and I would not recommend it (and that is what I was trying to say). The global standard of selling speaker cables in jackets with two closely adjacent + and - wires is still the current best practice and the "right" approach to get the equipment to perform according to the manufacturer's intent.

I know Al will agree with me on this one, as he is a EE and all audio equipment is designed to be hooked up with connections that are as transparent as possible.