When brief bursts of musical energy occur, SITs react with rounded waveform tops instead of sharp and hard clipping of solid-state. SITs have a curve which looks a lot like a triode vacuum tube; low at first and climbs steadily. The distortion curve is similar, a steady rise instead of a valley with high distortion at both ends.
When brief musical energy surges occur, SITs react with rounded waveform peaks instead of the sharp clipping characteristic of solid-state devices. The response curve of SITs is comparable to that of a triode vacuum tube, initially low and then increasing steadily. The distortion pattern shares similarities with this curve.