"Class A" compressors?

[McLilith]

Alright.. I am not so worried for a compressor cirquit to be not 100% efficient with power. How many watts will it consume, maybe one?

Perhaps much less than that. It all depends on the particular circuit design.

So I understand a "class A" compressor does not have normal opamps inside. Would a standard opamp be of the balanced push-pull type then, with one doing the plus phase and another doing the minus phase?

If you mean that one op-amp does half the signal, and another op-amp does the other half of the signal (like AB transistor or tube circuits), then the answer is generally "no". The AB circuitry is contained inside a single op-amp integrated circuit. Because of this, all the op-amps that I've ever had the pleasure of using, introduce an element of AB amplifier topology into whatever circuit they are used in. Sometimes this might be an issue for some people, but it usually isn't.

take care,
McLilith

[Tubeman]

So I understand a "class A" compressor does not have normal opamps inside. Would a standard opamp be of the balanced push-pull type then, with one doing the plus phase and another doing the minus phase?

Class A can be push-pull or single ended. Read this: http://www.aikenamps.com/ClassA.htm there's a good info on amplifier classes.