About power amp step response etc. :-)

[PMA]

It is also the feedback stability that counts, is not it?

This amp has no global feedback, and Zout is about 0.03 ohm.

The load may seem impossible, but some of the full range electrostats have quite pure capacitance up to some 10uF.

 

[syn08]

It is also the feedback stability that counts, is not it?

This amp has no global feedback, and Zout is about 0.03 ohm.

The load may seem impossible, but some of the full range electrostats have quite pure capacitance up to some 10uF.

A 10uF load would require much more current (hence more output devices) or a larger coil (hence limited rise/fall times). As I do not plan to sell my amps, I design them for regular speakers, 2 ohm minimum impedance including the phase shift. That is, the protection kicks in for loads around 1.8 ohm. That's where the 24A number comes from and so does the number of output devices (3). But then 50nS rise/fall time is a clear overkill so if I would have to feed electrostatics of the worse kind I would simply rise the output coil value to maybe 2uH. This and the input filter will provide enough room to feed those crazy loads, up to the nominal power.