The circuit can be modified to include {HEAD ~ a multiplication unit} for multiplying the input signal, the first delayed signal or the output signal by {TAIL ~ a predetermined constant} to obtain a desired direct current gain 
The circuit can be modified to include { HEAD ~ a multiplication unit } for multiplying the input signal , the first delayed signal or the output signal by { TAIL ~ a predetermined constant } to obtain a desired direct current gain
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH