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