Isolation transformer -low cost power conditioner?

Not enough current capability for a power amp.I have tried one and if it gets too hot you can tell it is not right.Does not really purify anything, just isolates and noise still can get through. Most of them have a fairly loud mechanical buzz.

I'm afarid I'll have to disagree with Don on all counts.

Current: You can get one that will handle just about any current you can imagine. If it gets too hot you are using one that is too small for the job. There are others but Furman used to make one that could handle 30 amps, big enough for most applications.

Filter: The transformer by itself will have some filtering capability. A transformer designed to pass 60Hz probably won't do as well at higher frequencies, thus providing some filtering. It would be very easy to add some capacitance to either or both sides to increase the effectiveness. Not something to take lightly but it can be done.

Noise: A well designed transformer that is used within its design parameters will not buzz. Torroidal transforms can buzz if the AC line is polluted with noise from things like light dimmers.

The original question about low cost? You need to define "low cost" as that is a very relative term.