second encoder means for binary encoding an output signal from said second means with {HEAD ~ a single threshold level} proportional to {TAIL ~ a level} of said signal from said first means; and 
proportional to
second encoder means for binary encoding an output signal from said second means with { HEAD ~ a single threshold level } proportional to { TAIL ~ a level } of said signal from said first means ; and
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH