Help with vertical Bi-Amping

To me Vertical biamping would imply one amp for the lower (BOTTOM) freqs and another for the upper (TOP) freqs. But this is unfortunately NOT the "definition". It is not about amplifier tiering. Vertical here means one amp drives one entire speaker (top-to-bottom) frequencies and the other amp the other speaker. It is such a confusing terminology that I wish were never "invented".

This configuration has the advantage of greatest channel separation. The downfall is that both amps have to be exactly matched and they have to handle the entire band which eliminates the optimization of finding amps that work so very well for one band or the other.

In any configuration, I feel that biamping only benefits the system greatly when you have optimized the speakers about as good as you can with one amp - you have reached that limit. Putting 2 mediocre amps and a mediocre active crossover (if this is used instead of the passive crossover in the speakers), and the extra cables, etc., will only result in not as good a sound as you already have.

John

John

John is right. You are actually talking about horizontal bi-amping. if you cannot find identical amp, you will need an active crossover.

thanks guys, guess I wasnt thinkin far enough outside of the box, by the way how complex are active crossovers, and what all is involced with speakers, do you need to Dig inside of speakers and change the internal crossovers? thanks again Chad

One point that is often over-looked is the reduction in IIM distortion (interface intermodulation distortion) when speakers are biamped. This includes passive biamping with the speaker cross-overs. The speaker is not just a "motor". It is also a generator. It is constantly feeding spurious energy back into the amplifier. This energy is generated by the moving mass of the speaker drivers exiting the resonance peaks. Some of this energy is dissapated by friction as heat, some of it is fed back into the amp as a back EMF. The woofer with the most mass generates a lot of this energy. ANY non-linear component that this back EMF and the audio signal both pass through will result in cross-modulation products. When you bi-amp, none of the back EMF from the woofer can cross-modulate with the mids and highs; only with the bass. If you have ever experienced a burst of grating distortion that seems to coincide with certain bass notes you probably have experienced this kind of distortion. There is a very good discussion of this in the current (May) issue of AudioXpress.