Why do you think Bi-Wiring improves the sound ?

Considering that the feedback changes the effect of this resistor and makes it approach 0 ....

... and the load changes the feedback.

Historically this was never provided for bi-wiring, it was provided for Bi-Amping to reduce IM distortion and/or tailor amps to frequency range.

Systems designed to be bi-amped typically do not have internal crossovers. Systems with properly designed passive crossovers make poor candidates for bi-amping. Amplifier response varies with the load and driver response varies in combination with the driving amplifier and the parallel loads of the additional drivers.

This is quite easy to demonstrate:
2 identical power amps y'd from the source.
Drive the LS full range, bi-wired and bi-amped. There are 3 distinct responses, all easily identifiable.

Some drivers make poor bi-amping candidates without either active or passive equalization other than crossover slopes.

There is no, and never has been, any free lunch.

@heaudio123
I don't understand why you are so antagonistic. My examples are stated necessarily simplistic to communicate concepts. Are you a manufacturer? Audio sales?
"atmasphere, as someone who designs amps (for many applications), I cannot agree at all with your comment w.r.t. amount of feedback and sounds profile." from  https://forum.audiogon.com/discussions/it-looks-like-a-debate-to-me?page=2

What amps, pray tell!

@bigkidz i am in hotel California for now..... seattle when I can travel safely, since you have the lovely 5a I will send them to you shipping gratis- just listen and enjoy :-)

My Reference power amps don’t have emitter resistors :-) and certainly no global feedback...

The whole reason speakers started to have 2 sets of terminals was not for bi-wiring, but for bi-amping. Current starvation in the output devices, increased IM in the output stage from non-linear effects at higher currents, and IM from modulation of the power supply from bass frequencies is eliminated from the amplifier that only supplies the typically much lower current mids/highs. Voltage induced distortion effects at other stages in the amplifier will still occur of course, but traditionally this has been less of an issue.


There is no technical justification for "systems with properly designed passive crossovers make poor candidates for bi-amping", since the benefits are not for the speaker, they are for improvements in amplification. For amplifiers with lower THD at high power (typically because of high distortion near the 0-crossing), the high frequency amplifier will increase in IM, but will reduce in THD by riding on the high voltage bass signal. That same amp with an input passive filter for the highs can have sonically unacceptable distortion characteristics on real music.

Systems designed to be bi-amped typically do not have internal crossovers. Systems with properly designed passive crossovers make poor candidates for bi-amping.

The parallel loading of the additional drivers on the amplifier is almost always negative (see above) if your goal is accuracy and un-colored sound. Bi-Wiring only adds a very small amount of isolation, basically the impedance of one set of wires, which with competent wires is very little. Bi-Amping completely electrically (and back EMF) decouples the two driver sets.

driver response varies in combination with the driving amplifier and the parallel loads of the additional drivers.

Which loudspeaker manufacturer first put biwire binding posts on the back of their speakers?  Anybody know?