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