TEACH ME ABOUT BI-WIRE

Liguy - You realize that when bi-wiring both the high and low side of the crossovers are still hooked together. It's just at the amp instead of the speaker. You can accomplish the same thing with larger speaker wire.

Damping factor is the ability of the amplifier to maintain a constant output voltage as speaker impedance changes. It can be very high in SS amps and good enough with tubes.

Take a woofer with a powerful motor and connect its terminals together. When you move the cone it feels like there is a shock absorber connected. Its a very strong effect. As you move the cone a current is generated that opposes the motion of the cone. In a system this effect improves the accuracy of the cone movement. So, it would be nice if there were nothing to impede this correction current generated by the speaker itself. Decent sized speaker wire and reasonable amplifier damping factor help. Typically, far more resistance is created by the crossover networks themselves. The slightest driver efficiency mismatch will have required the speaker designers to provide resistance to the louder driver. Resistance is unavoidably high throughout crossover regions.

Fully utilizing an amplifiers damping factor may be achieved with bi-amping or tri-amping, since there are no passive crossover components between the drivers and amplifiers. How much real world gain there is to bi-amping, I don't really know. I am undertaking a DIY speaker project shortly and it will be tri-amped with very high damping factor amps. When I am done with the project I still won't know ;-)

Just in case anybody missed it, Liguy's most recent post refers to bi-AMPING, not bi-WIRING. There's an important difference, as Steve points out.

i was under the impression that biwiring, in some cases, can be effective because the back-voltage going thru the wiring of the woofer is now separated from the wiring to the the tweeter, even tho it eventually meets up back at the amplifier. i believe that having the connection point several feet of wire away, at the amp, instead of at the speaker, can make a difference. i know my monitors sound better w/a stereo amp when bi-wired, as opposed to having a single run w/the speaker mfr's factory yumpers in place. but, perhaps its sonic degradation of the yumpers? or yust the fact that, when bi-wiring, i am doubling the quantity of copper cabling? i admit that i havent tried doubling the speaker-wire to only *one* set of terminals w/the yumpers in place...

doug s.

Liguy is right, it makes a big difference with Martin Logan speakers. The first set of Aerius i I tried out where set up for single wire only, I ordered Bi-wire option just in case it would benefit ( only 100.00 or so ) The new set came, I broke them in then bi-wired. Big change.

I disagree with almost everything Jostler, Stevemj have posted here, and so do the majority of high end speaker manufacturers, but they are entitled to their opinions.

The actual mechanics of bi-wiring, and special design of seperate crossovers that control what signal travels down each cable are covered in detail on many differnt web sites.

The only question to the customer is do the benefits of bi-wiring overcome the additional cost involved with two sets of cable. Or another way of putting it is do two sets of $500 cable sound better than one set of $1000 cable.