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