Diagnostic Articulation Testing in the Design of Speech-Processing Devices
Michael H. L. Hecker, Douglas L. Phyfe · The Journal of the Acoustical Society of America · 1963
The utility of simplified nonsense-syllable tests containing stimuli of the form /h∂′CVC/ for measuring the performance of existing speech-communication links on specific consonant and vowel features has been demonstrated [K. N. Stevens et al., J. Acoust. Soc. Am. 35, 1116(A) (1963), Paper G10]. It has been suggested that selected nonsense-syllable material may also be used repeatedly on experimental speech-processing devices for the purpose of optimizing certain critical adjustments or design parameters. The present paper illustrates this application of diagnostic articulation testing by considering the design of a new voicing indicator for a digital channel vocoder. An initial test revealed a number of “voicing” errors among fricative consonents. These errors could be reduced by modifying the characteristics of a low-pass filter, as indicated by a second test, but the changes that were made increased “place” errors among stop consonants. The third test showed that the introduction of a slight delay could check these errors.