Cross-language differences in how voice quality and f 0 contours map to affect.

The relationship between prosody and perceived affect involves multiple variables. This paper explores the interplay of three: voice quality, f 0 contour, and the hearer's language background. Perception tests were conducted with speakers of Irish English, Russian, Spanish, and Japanese using three types of synthetic stimuli: (1) stimuli varied in voice quality, (2) stimuli of uniform (modal) voice quality incorporating affect-related f 0 contours, and (3) stimuli combining specific non-modal voice qualities with the affect-related f 0 contours of (2). The participants rated the stimuli for the presence/strength of affective colouring on six bipolar scales, e.g., happy-sad. The results suggest that stimuli incorporating non-modal voice qualities, with or without f 0 variation, are generally more effective in affect cueing than stimuli varying only in f 0. Along with similarities in the affective responses across these languages, many points of divergence were found, both in terms of the range and strength of affective responses overall and in terms of specific stimulus-to-affect associations. The f 0 contour may play a more important role, and tense voice a lesser role in affect signalling in Japanese and Spanish than in Irish English and Russian. The greatest cross-language differences emerged for the affects intimate, formal, stressed, and relaxed.

Voice quality in affect cueing: does loudness matter?

In emotional speech research, it has been suggested that loudness, along with other prosodic features, may be an important cue in communicating high activation affects. In earlier studies, we found different voice quality stimuli to be consistently associated with certain affective states. In these stimuli, as in typical human productions, the different voice qualities entailed differences in loudness. To examine the extent to which the loudness differences among these voice qualities might influence the affective coloring they impart, two experiments were conducted with the synthesized stimuli, in which loudness was systematically manipulated. Experiment 1 used stimuli with distinct voice quality features including intrinsic loudness variations and stimuli where voice quality (modal voice) was kept constant, but loudness was modified to match the non-modal qualities. If loudness is the principal determinant in affect cueing for different voice qualities, there should be little or no difference in the responses to the two sets of stimuli. In Experiment 2, the stimuli included distinct voice quality features but all had equal loudness to test the hypothesis that equalizing the perceived loudness of different voice quality stimuli will have relatively little impact on affective ratings. The results suggest that loudness variation on its own is relatively ineffective whereas variation in voice quality is essential to the expression of affect. In Experiment 1, stimuli incorporating distinct voice quality features consistently obtained higher ratings than the modal voice stimuli with varied loudness. In Experiment 2, non-modal voice quality stimuli proved potent in affect cueing even with loudness differences equalized. Although loudness per se does not seem to be the major determinant of perceived affect, it can contribute positively to affect cueing: when combined with a tense or modal voice quality, increased loudness can enhance signaling of high activation states.

Inverse filtering of nasalized vowels using synthesized speech.

The present study examines the extent to which increased nasal coupling affects estimates of glottal parameters derived from inverse filtering based on an all-pole assumption of the vocal tract. A series of steady-state tokens for five Swedish vowels were synthesized using the HLsyn quasi-articulatory synthesizer (Sensimetrics, Malden, MA). For each vowel, the parameter controlling the cross-sectional area of the nasal aperture, an, was systematically varied, while the other HLsyn parameters were kept constant. The resultant pressure signal for each utterance was subsequently inverse filtered, and estimates were made of five glottal source parameters (EE, RG, RA, RK, and OQ) derived from fitting the Liljencrants and Fant source model to the inverse filtered signal. The results show that when analyzing nasalized vowels using inverse filtering based on an all-pole assumption of the vocal tract, the RA parameter estimate--a main determinant of the source spectral slope--can be adversely affected by nasal coupling. The errors in our estimates were particularly high for the high vowels: this was true not only for RA, but for all the parameters measured. However, with the exception of the distortion in the RA estimate, the effects were relatively small, regardless of the degree of nasal coupling.