[sdiy] Looking for Speech Synth Chips! Can you help me?

[Richard Wentk]

At 17:26 15/09/2003 +0000, jbv wrote:

>Sure...
>I actually spent some time wondering what would be the best
>choice of design for the VC BP filter bank (especially coz I'm
>not an analog wizzard)... I finally decided that the first step
>was to check if the concept would work, and decided to prototype
>that thing with a set of CEM3350 chips.

You'll find that real formants are only approximately like simple bandpass 
filters. When you speak the resonances occur in different parts of the 
mouth/nasal cavity at different times, and morphs between these resonaces 
can contribute as much to the character of the sound as the location of the 
resonances.

A more fertile approach would be to sample various people talking, chop out 
the phonemes and cross-synthesise those digitally with an input signal to 
create a talking result.

There's also a technology called Linear Predictive Coding (LPC) which is 
used to model filter characteristics in speech-related systems.

Alternatively just use a vocoder - it's much quicker. ;-)

Seriously, storing/sequencing the control signals created by the analysis 
bank in a vocoder will probably give you better results than any other 
analogue technique.

Richard