I have built a few pverdrives not using various types of clipping. The MDMA (wampler euphoria) is the only one I have built so far that has a setting with just the op amp clipping.
Does anybody know of over circuits that do?
I was thinking this also. I believe the clean rat from the Deucetone rat is just a rat without clipping diodes.
I think most of the LM386 like the Acapulco gold, clari not ect circuits don't use diodes also you would probably have to set them in the low gain mode or they become distortion pretty quick tho.