I have put together a computer based piano, made out of a Fatar keyboard,
and a low noise Via C3 processor. I'm running the "Steinberg Grand" VSX
piano simulation. Amplification is provided by a small Sugden amp that runs
hot.

I would like the operational characteristics of this piano to be as close as
possible to a regular acoustic piano. One of the characteristics of a "real"
piano is that one can simply walk up to it and play it. However, I don't
want the amp powered up all the time, because it draws far more power than
the computer.

Any suggestions for synchronizing the power status of the amplifier with use
of the piano?