SoundshaperLogo
SOUNDSHAPER: CDP REFERENCE

VOWELS - impose vowel formants


CDPLOGO
SPECTRAL
FILTER
hilite vowels
PREVToIndex
VOWELS
 NEXT

SPECTRAL > FILTER > VOWELS >

SUMMARY
VOWELS attempts to impose the formant characteristics associated with vowels on to the sound, in a time-varying manner.

PARAMETERS
 vowels  Datafile of times (in secs., increasing from 0) and vowels, the latter coded as:
ee: as in 'heat'     i:  as in 'hit'        e:  as in 'pet'      ai: as in 'hate'
a:  as in 'pat'       ar: as in 'heart'    o:  as in 'hot'      or: as in 'taught'
oa: as in 'boat'     u:  as in 'hood'    oo: as in 'mood'
xx: as in Southern English 'hub'       x:  neutral vowel in 'herb' or 'the'
(The implied pronunciations here are English.)
Example
:
0         ai
0.7      ai
0.72    ee
1.44    o
2.17    oa
The vowel data values are continuous from one time to the next; e.g. the vowel from time 0 to 0.7 is static, but between 0.72 and 1.44 changes from ee to o.
 half width  of formant peaks in Hz, as fraction of formant centre frequency
Range: 0.01-1-10 Default: 0.25
 steepness  Resonance of formant peaks, similar to 'Q' in filtering (smaller is narrower; more sharply defined).
Range: 0.01-1-10 Default: 3.0
 peak range  Ratio of (max) peak height to (max) total range of peak height 
Range: 0-1, default 0.95. 
 threshold  Proportion of spectral window level compared with vowel envelope level  
Range: 0-1, default 0.5.
 
NOTES
To be convincing, the source sound must have a wide range of frequencies. For example, it is not possible to bring out the vowel 'oo' (formant centres 320 and 800 Hz), if there are no frequencies present below 1000Hz.

Most of the parameters, apart from vowels, are over-detailed and work well enough with their default values. Steepness may be worth setting to control the width of the peaks.

The program clearly succeeds in colouring the sound, 
but direct vocoding with a spoken/sung vowels may often be more convincing. Also note the sister program Pitch-Vowels.

© Ensemble Software and Composers Desktop Project 2014