Each diode 162, 164 and 166 conducts in the forward direction and thereby establishes a clipping level at approximately +0.5 volts change in gate swing to emulate {HEAD ~ distortion} associated with grid conduction in {TAIL ~ a tube amplifier} 
Each diode 162 , 164 and 166 conducts in the forward direction and thereby establishes a clipping level at approximately +0.5 volts change in gate swing to emulate { HEAD ~ distortion } associated with grid conduction in { TAIL ~ a tube amplifier }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL