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Re: Votrax chip SC01/SC02



Allen Bong wrote:
On Aug 28, 7:13 am, "Michael J. Mahon" <mjma...@aol.com> wrote:

Allen Bong wrote:

Hi Group,

Any one still remember the votrax speech synthesizer chip SC01 and
SC02 used in the mocking board sound card?  Does any one know where I
can get software to drive this chip.  Besides English, are there any
variants with other languages?

The SC-02, more commonly known as the SSI-263, is a phoneme- or
allophone-based synthesizer with 64 discrete phonemes built in.

To produce words, strings of phonemes must be produced, with volume,
pitch, and duration controlled by an attached computer.

Although tables of "pre-compiled" words may be created, the most
common use of the chip on the Apple II was in "text-to-speech" mode,
in which a set of rules is used to generate phoneme strings from
ASCII-coded English text.  With different tables, many other languages
could also be pronounced, but there may be missing or subtly different
phonemes for some other languages, or the tonal controls may be too
coarse for some cases.

There were also some phoneme sequencing rules that were required
(think of a peephole optimizer) to prevent certain "pops" and
other artifacts resulting from certain phoneme transition bugs.
(The SC-01 had different, and perhaps fewer, such bugs.)


I have found a site using Z80 to control the SC01 but I think it was
too complicated.

http://trshare.triumf.ca/~amaudruz/votrax/index.html

This is a complete single-board computer for controlling the SC-02
in an editable fixed-vocabulary synthesizer.  This would be appropriate
for, say, a menu response system.


What are  the modern chips with equilvalent functions and are well
supported?

They are largely obsoleted by fast general purpose processors and
inexpensive DSPs, which make speech synthesis entirely a software
issue.

These speech synthesis chips were primarily useful when the
microcontrollers and computers were too slow to do the synthesis
computations in software.

Thanks Michael, that's a lot of informations for me.  How's the
quality of speech compared to SAM - Speech Automated Mouth ?

The quality is very similar, since they are both phoneme synthesizers.

Are the software comptible with each other?

The text-to-phoneme translation is almost identical, since it's
derived from the same Navy code base, but the encoding of the
phonemes may (or may not) be different.

BTW, SAM is an example of how finesse, even on a 1MHz machine with
no DAC, cound do speech synthesis without dedicated hardware!

-michael

NadaPong: Network game demo for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
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