{TAIL ~ an analog} to digital converter that converts {HEAD ~ an analog acoustic input signal} into a digital input signal 
{ TAIL ~ an analog } to digital converter that converts { HEAD ~ an analog acoustic input signal } into a digital input signal
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH