The main path amplifies {HEAD ~ a power level} of {TAIL ~ an input signal} to generate a path turning signal 
The main path amplifies { HEAD ~ a power level } of { TAIL ~ an input signal } to generate a path turning signal
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH