The system then determines {HEAD ~ the power spectral density} of {TAIL ~ the audio signal} from the calculated power spectral density of the speech signal 
of
The system then determines { HEAD ~ the power spectral density } of { TAIL ~ the audio signal } from the calculated power spectral density of the speech signal
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH