{TAIL ~ A comparator} receives {HEAD ~ a threshold value} and compares each of the intermediate amplitude values to the threshold value 
{ TAIL ~ A comparator } receives { HEAD ~ a threshold value } and compares each of the intermediate amplitude values to the threshold value
TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH