a dedicated piezo amp.

[Pbassred]

Not that I would EVER want to do it of course, but in an effort to understand........
Since Piezos are a "capacitive load" (what?), what would be the effect of hooking an amp into one of those piezo tweeter boxes with no other speaker fitted. Naturally this would be part of a multi amp system.

How would you assess the right load?
How would you know that the amp is the right size?
piezos are usually put with cone drivers, and the amp chosen to match the driver. Does this mean that piezo power is free?

Naturally this is a ficticious system, so don't waste your time telling me not to do it!

[Ron E]

It depends on the amp. Some amps will drive a capacitive load all day, others will oscillate due to the low impedance at high frequencies - the high frequency oscillation will fry the outputs relatively quickly if you have it really cranked. You won't know which category your amp is in until you try it. Usually one puts in a series resistor to limit the impedance drop at high frequencies and thus the oscillation.

These are effectively an open circuit at low frequencies due to their high impedance, so they don't need a crossover when combined in parallel with a woofer - but their integration will be better if you do use a crossover. No, the power is not free, it is really just taking most of whatever is delivered to the woofer at the frequencies where it has a lower impedance than the woofer.

Piezos mostly sound like c.r.a.p. so any benefit to driving them with their own amp is pretty minimal. Bullet tweeters are cheap and loud, so why use a piezo?

[mashaffer]

Hmmm... makes me wonder if a tube amp without an output transformer might work.

mike