Institute for Telecommunication Sciences
the research laboratory of the National Telecommunications and Information Administration

Institute for Telecommunication Sciences / Research Topics / Audio Quality Research / Example speech files: Spectral Companding and Speech Coding

Example speech files: Spectral Companding and Speech Coding

For full details, see: S. Voran, "Observations on Frequency-Domain Companding for Audio Coding," Proceedings of the Eighth IEEE Digital Signal Processing Workshop, Bryce Canyon National Park, Utah, August 1998.

Speech Coder Alpha Female Talker Male Talker
No Coder 1.0 DS98043A.WAV DS98043B.WAV
PCM
4 bits/sample
1.0 DS98043C.WAV DS98043F.WAV
0.6 DS98043D.WAV DS98043G.WAV
0.2 DS98043E.WAV DS98043H.WAV
ADPCM
2 bits/sample
1.0 DS98043I.WAV DS98043L.WAV
0.8 DS98043J.WAV DS98043M.WAV
0.6 DS98043K.WAV DS98043N.WAV
RPE-LTP (Full rate GSM)
≈ 1.6 bits/sample
1.0 DS98043O.WAV DS98043R.WAV
0.8 DS98043P.WAV DS98043S.WAV
0.6 DS98043Q.WAV DS98043T.WAV