Help with bi-amping

A good quality crossover is the Bryston 10 - it retails in the 1400-1600 range. The Krell is better but a lot more - see if you can borrow a Rane crossover 300-550 from a local music store or rent it if a high end dealer will not loan you an active one. It can at least give you an idea of what an active crossover of a higher quality can do for you as far as control and frequency separation are concerned.

I disagree that using two 100 watt amps or two channels of a 100 watt ampis the same as a 100 watt amp. As evidence, often times one will see that an amp can be bridged to provide (at least) double the power of the two channel mode.

Many experts will disagree with that. That's why I said you need to compare 2 100 Watt amps to a 200 watt amp. John Dunlavy believes that the 200 watt amp will win all the time. (SET's not included). A lot of people claim bi-amping is better, but nobody ever wants to do a valid comparison. Two 100 watt amps vs a single 100 is not a valid comparison.

It's sort of an interesting set of tradeoffs comparing the two. The two single amplifiers mean that the high and low frequencies are not intermodulating, which will produce a better sound. This is the opinion I have seen most often from "experts." The single amplifier on the other hand will better divy up the power between the upper and lower frequencies, which will probably let you drive the speakers to a higher SPL. There is also a consideration in that the quality of components used by manufacturers tends to improve with the power of the amplifier, so I don't think that a real world comparison of two 100 watt amplifiers to 1 200 watt amplifier would be an apples to apples comparison.

If that wasn't too clear, when you have two amplifiers connected independently you run out of steam whenever either one reaches it's power limit. On my system the passive crossover crosses over at about 120 Hz. I have seen 240-340 Hz mentioned as the point at which most music contains an equal amount of energy above and below. I can't confirm this, but it seems about right, and for the purposes of this discussion, the exact point really doesn't matter, just that it exists.

Putting these two things together, I think I would run out of power and start clipping on the top end before I ran out of power on the bottom end. Of course, the approach I used is to have more power available on both the top and bottom ends than my speakers can handle, so it really doesn't matter. :-)

Another factor to consider is that with the passive bi-amp system, you are well on the road to having active bi-amping and I have never seen anyone try to claim active bi-amping wasn't better with two 100 watt amps than a single 200 watt amp since this argument would ultimately reduce to the contention that passive crosovers are superior to active crossovers which would be a pretty tough proposition to sell. That is, assuming of course, that the amplifiers used were of the same quality.

Regards,
Greg

I find this thread interesting because Martin Logan has quite a bit of information claiming that the benifits of an active crossover are far more than outweighed by the negative aspects of adding another component into the signal path. It is also interesting that they incorporate a crossover in their Statement speaker system that is also available for the CLS2z's.