>
> > You'd need a sine wave source of fairly accurate frequency, and a
> > way to control the amp gain to set output voltage, and keep it
> > constant under load changes.
>
>         Very few inverters, at least the kind you'd find in a hardware store,
>generate sine waves, the usually generate some sort of "step wave" that has
>the same RMS as a "normal" sine wave, and that "kind of" looks like a sine
>when feeding "typical" loads.

True, and this is the only reason I can think of for using the audio amp
approach.

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