a plurality of level control units receiving {TAIL ~ said modified signals} and providing {HEAD ~ normalized modified signals} having a constant amplitude 
a plurality of level control units receiving { TAIL ~ said modified signals } and providing { HEAD ~ normalized modified signals } having a constant amplitude
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH