Automatic phonetogram recording supplemented with acoustical voice-quality parameters.

A new method for automatic voice-quality registration is presented. The method is based on a technique called phonetography, which is the registration of the dynamic range of a voice as a function of fundamental frequency. In the new phonetogram-recording method fundamental frequency (Fo) and sound-pressure level (SPL) are automatically measured and represented in an XY-diagram. Three additional acoustical voice-quality parameters are measured simultaneously with Fo and SPL: (a) jitter in the Fo as a measure for roughness, (b) the SPL difference between the 0-1.5 kHz and the 1.5-5 kHz bands as a measure for sharpness, and (c) the vocal-noise level above 5 kHz as a measure for breathiness. With this method, the voice-quality parameter values, which may change substantially as a function of Fo and SPL, are pinned to a reference position in the patient's total vocal range. Seen as a reference tool, the phonetogram opens the possibility for a more meaningful comparison of voice-quality data. Some examples, demonstrating the dependence of the chosen quality parameters on Fo and SPL are given.