Vocal registers revisited

Vocal registers revisited

Gerrit Bloothooft

Peter Pabon

Utrecht Institute of Linguistics OTS

The Netherlands

Vocal registers

Scientific agreement same mechanical principle of voice

production pulse- modal- falsetto- register

Singers terminology ‘sub’ registers: chest voice, middle

voice, head voice

Phonetogram

Display of all possible phonations X-axis: fundamental frequency Y-axis: sound pressure level

Unit: 1 dB x 1 semitone

Fundamental frequency (Hz)

Voc

al I

nten

sity

(dB

SP

L)

Sam

ple

Den

sity

Phonetogram sample density

Research goal

Use of phonetogram recordings to reconsider the vocal register terminology

Enriched phonetogram

Acoustic voice quality parameters added jitter

stability of fundamental frequency

crest factor differentiates between pulse-like and sine-like

relative rise timefast versus slow signal change in period

Displayed using colour scale

Data recording

For real-time presentation best jitter value last crest factor value last value of relative rise time

For post-recording processing median value of distribution

Real-time display of crest factor

Vo c

al I

nten

sity

(dB

SP

L)

Fundamental frequency (Hz)

Cre

st f

acto

r

Median smoothing of crest factor

Vo c

al I

nten

sity

(dB

SP

L)

Fundamental frequency (Hz)

Cre

st f

acto

r

Most significant changes

Description using

Iso-crest factor linesIso-jitter linesIso-relative rise time lines

Iso-crest factor lines

4 dB

6 dB

Vo c

al I

nten

sity

(dB

SP

L)

Cre

st f

acto

r

Fundamental frequency (Hz)

Iso-jitter lineV

o cal

Int

ensi

ty (

dB S

PL

)

Fundamental frequency (Hz)

3 %

Jitt

er (

%)

Iso-relative rise time lineV

o cal

Int

ensi

ty (

dB S

PL

)

Fundamental frequency (Hz)

Rel

ativ

e ri

se ti

me

(%)

6 %30

20

10

0

New representation

Areas defined by iso-parameter lines crest factor < 4 dB crest factor > 4 dB, < 6 dB crest factor > 6 dB jitter < 3 % relative rise time < 6 %

Areas in the phonetogramV

o cal

Int

ensi

ty (

dB S

PL

)

Fundamental frequency (Hz)

Jitter > 3%, unstable

RRT < 6 %pressed-like Crest factor < 4 dB

sine-like

Relation to vocal registers

Ask subject to sing in specific register only and determine register-phonetogram

Map these register boundaries on full phonetogram

Fundamental frequency (Hz)

Vocal registers in the phonetogram

Falsettoupper boundary

Modallower boundary

Chest voiceboundary

Vo c

al I

nten

sity

(dB

SP

L)

First observations

High modal boundary corresponds with iso-crest factor = 4 dB

Upper falsetto boundary corresponds in part with iso-crest factor = 6 dB

Chest voice boundary corresponds with iso-crest factor = 6 dB

Conclusions

Close relation between iso-crest factor lines and register boundaries

Chest voice may well have a perceptual basis

Low falsetto boundary not related to any of the measures used

Systematic research needed

ExamplesV

o cal

Int

ensi

ty (

dB S

PL

)

Fundamental frequency (Hz)