Spectra of some Stop Consonants
Morris Halle, Caldwell P. Smith · The Journal of the Acoustical Society of America · 1953
Although considerable data exist describing the spectra of vowel sounds, little information is available with regard to the consonants. Such information is obviously of great importance to all who are interested in the study of the acoustical properties of speech. A study has been made of the spectra of some of the stop consonants, using a refined measurement technique that permits precise separation of the consonant from its context. From a catalog of syllables recorded on magnetic tape, loops of tape were prepared, each containing a single syllable. A tone burst was added immediately preceding the syllable, to provide precise timing of both an oscillographic display and the segmentation circuitry. By observing the filtered and rectified speech wave on a long-persistence cathode-ray tube, it was possible to identify the characteristic vowel and consonant patterns, as well as to separate the burst from the aspiration in the stop consonants. Using visual and aural observation of the speech signal as a guide, it was also possible to precisely adjust timing circuits so as to switch the speech signal and the measuring circuitry on and off during that interval of the speech sound for which a spectrum was to be ascertained. Some of the results obtained by these measurements, as well as details of the measuring device, are presented.