This paper is a phonetic investigation of the genre of radio newsreading on the Canadian Broadcasting Corporation (CBC) from 1937 to 1987. Recorded newscasts from the first, third, and fifth decades of CBC history are examined. Brief histories of CBC Radio news and of the Office of Broadcast Language are included, and the bibliography brings together much scattered reference material on CBC language. Traditional auditory evaluations of selected aspects of voice quality settings, vowel quality, and voice dynamics are supplemented by instrumental measurements.

The descriptive terminology of Laver (1980) is applied to the voice quality settings. The majority of newsreaders examined display the vocal settings of lowered larynx, open jaw, and the use of creaky phonation. This configuration enhances vocal resonance and is shown to be an established newsreading model, perceived as suitable to the authoritative presentation of information. The patterns of vocal settings identified for three test decades (1937-47, 1957-67, 1977-87) are supported by the results of acoustic analyses.

Individual, group, and across-group statistical tests were executed on the results of acoustical waveform analyses of the peripheral vowels /*a *a u/ produced by each newsreader. To test vowel quality as a sociolinguistic variable, the CBC formant data were compared with compatible /*3.A:ehp3. :hp3.O:ehp3. u/ data from informants of the Survey of Vancouver English(Gregg, 1984). The results show that the speech of CBC Radio newsreaders cannot be associated with any particular SES class of the Vancouver Survey.

As a result of the extensive variation in production found for both informant groups, the high back vowel phoneme /u/ remains ill-defined for Canadian English.

The voice dynamic component in CBC Radio newscasts has changed over the years. Measurements of speech rate show that the duration of pauses post-1966 are dramatically shorter than those pre-1966. Sentence length is shown not to have changed considerably, but phrases have been lengthened and pauses shortened.

A marked reduction in the percentage of silent time within the newscast has been the result. It is suggested that pitch fluctuations are now used more extensively than pausing to structure the text orally. Despite the changes in continuity, the articulation rate of the newsreaders, measured in syllables per second, has remained constant. These results indicate that the newsreaders are exceptionally skilled speakers.

The prevalent voice settings and the averaged acoustical measurements for CBC vowels are presented as representative of a readily identifiable and publicly recognized standard of formal spoken Canadian English.