Fred Durst. Mario Balotelli. Colin Farrell. Criss Angel. Kid Rock. Jack Osbourne. Val Kilmer.
The overdrive is produced using two silicon diodes in anti-parallel arrangement into the negative feedback circuit of a operational amplifier "op-amp" circuit, to produce soft, symmetrical distortion of the input waveform. A "drive" potentiomenter in the feedback path provides variable gain. The original based circuit uses transistor buffers at both the input and the output, to improve impedance matching.
Thought of this way, it is said that this "preserves the original dynamics of the input signal which otherwise would get lost at the threshold of clipping" and "avoids muddiness and vastly improves clarity and responsiveness.