D. Byrne et al., AN INTERNATIONAL COMPARISON OF LONG-TERM AVERAGE SPEECH SPECTRA, The Journal of the Acoustical Society of America, 96(4), 1994, pp. 2108-2120
The long-term average speech spectrum (LTASS) and some dynamic charact
eristics of speech were determined for 12 languages: English (several
dialects), Swedish, Danish, German, French (Canadian), Japanese, Canto
nese, Mandarin, Russian, Welsh, Singhalese, and Vietnamese. The LTASS
only was also measured for Arabic. Speech samples (18) were recorded,
using standardized equipment and procedures, in 15 localities for (usu
ally) ten male and ten female talkers. All analyses were conducted at
the National Acoustic Laboratories, Sydney. The LTASS was similar for
all languages although there were many statistically significant diffe
rences. Such differences were small and not always consistent for male
and female samples of the same language. For one-third octave bands o
f speech, the maximum short-term rms level was 10 dB above the maximum
long-term rms level, consistent across languages and frequency. A ''u
niversal'' LTASS is suggested as being applicable, across languages, f
or many purposes including use in hearing aid prescription procedures
and in the Articulation Index.