first differential amplifier means for generating a left right differential output signal which is {TAIL ~ a function} of the difference in amplitude of {HEAD ~ said left and right output pulses} 
first differential amplifier means for generating a left right differential output signal which is { TAIL ~ a function } of the difference in amplitude of { HEAD ~ said left and right output pulses }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD