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Expressive Vocalization System 191

Table 11.4
Percent contributions of vocal affect parameters to DECtalk synthesizer settings. The absolute values of the
contributions in the far right column add up to 1 (100%) for each synthesizer setting. See the equations in
Section 11.3 for the mapping. The equations are similar to those used by Cahn (1990).

Controlling Vocal Percent of
DECtalk Synthesizer Setting DECtalk Symbol Norm Affect Parameter(s) Control
average-pitch ap 0.51 average pitch 1
assertiveness as 0.65 final lowering 0.8
contour direction 0.2
baseline-fall bf 0 contour direction −0.5
final lowering 0.5
breathiness br 0.46 breathiness 1
comma-pause :cp 0.238 speech rate −1
gain-of-frication gf 0.6 precision of 1
articulation
gain-of-aspiration gh 0.933 precision of 1
articulation
gain-of-voicing gv 0.76 loudness 0.6
precision of 0.4
articulation
hat-rise hr 0.2 reference line 1
laryngealization la 0 laryngealization 1
loudness lo 0.5 loudness 1
lax-breathiness lx 0.75 breathiness 1
period-pause :pp 0.67 speech rate −1
pitch-range pr 0.8 pitch range 1
quickness qu 0.5 pitch discontinuity 1
speech-rate :ra 0.2 speech rate 1
richness ri 0.4 brillance 1
smoothness sm 0.05 brillance −1
stress-rise sr 0.22 accent shape 0.8
pitch discontinuity 0.2

weak. It can also be used as an auditory cue to regulate turn taking. A strong final lowering
can signify the end of a speaking turn, whereas a speaker’s intention to continue talking can
be conveyed with a slight rise at the end. This parameter strongly contributes to DECtalk’s
assertiveness setting and somewhat to the baseline-fall setting.

• Pitch Range Measures the bandwidth between the maximum and minimum f 0 of the
utterance. The pitch range expands and contracts about the average f 0 of the pitch contour.
It varies directly with DECtalk’s pitch-range setting.

• Reference Line Controls the reference pitch f 0 contour. Pitch accents cause the pitch
trajectory to rise above or dip below this reference value. DECtalk’s hat-rise setting very
roughly approximates this.