In {TAIL ~ principle}, however, the method can also be realized in that the distorted signal S4 is obtained directly from {HEAD ~ the linear input signal} S1 
In { TAIL ~ principle } , however , the method can also be realized in that the distorted signal S4 is obtained directly from { HEAD ~ the linear input signal } S1
OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH