"Bob Gough" wrote in message
om...

First of all, to do what you describe (double the max. voltage) the
amplifiers
would be connected in series not in parallel.

No. It's a bridge configuration.

Secondly, as you say, both
amplifiers are fed the same input signal in opposite phase, not different
signals as has been suggested.

That makes no difference. In fact, when both aplifiers get the same,
opposite signal, it stresses the amps most, because if one outputs maximum
positive voltage, the other outputs maximum negative. With different
signals, the difference in voltages is always lower on average.

Which reminds me of a configuration that was quite popular many years ago:
to create some sense of depth in a stereo signal, some people connected a
third speaker between the 'hot' ends of the stereo outputs.

So again, it is quite possible, the only requirement is that both devices
have roughly the same power output capability.

Meindert