Powering non-speaker appliances with an amp

[cspirou]

I just have a hypothetical I was thinking about. Say you have a high powered amp in the range 2000-3000 watts. If you fed the amp with the appropriate 50Hz/60Hz signal could you power an appliance, like a drill, by connecting it to the speaker output? Is there something fundamentally different about speakers that this wouldn't work?

If this is too extreme then scale it down to something that just requires a 15VAC power source, like a fan.

 

[Elvee]

It can be done, and is actually done: that's the way some high quality AC lab supplies work.
Generally, it is some energy-efficient class D style amp, but the plain class AB version also exist.

 

[scopeboy]

I do this all the time in the lab for testing circuitry that has to work on American 60Hz mains. I use a 400W Class-D module for larger circuits and a regular MOSFET amp for smaller ones.

None of the amps I have to hand can manage 120V RMS, let alone 240, so I use a step-up transformer.

 

[Charles Darwin]

I understand EMT used a power amp to drive the motor in their 950 dd turntable.

 

[JonSnell Electronic]

In its infancy the Amacron (Crown now) DC300 comes to mind. It is a servo amplifier, class b.