I found this circuit that uses an opamp with a pair of diodes in antiparallel in the feedback loop to reduce the opamp gain when the signal rises to a certain level. I would think that this is more of a limiter than a compressor, since it cuts in at 0.6V and stays that way as long as the signal level is above 0.6V. The author claims that it transitions smoothly and gives good results.
But my main interest is not so much about the performance, but how I can get this same principle to work on a simple 1 transistor circuit. I came up with the schematic ( see attached) that might work, however I haven’t tried it yet.
