(2) Video Game Sound + Speech ( was RE: 80's Video...)

Clive Jones CJones at sni.co.uk
Thu Feb 29 02:50:00 CET 1996

Hi Chaps

> anybody remember arcade games back in the 80's?  Remember the cool   
> they made?  I mean, I know they we're very limited, but to me, that
> crudeness gave them their charm.
> So, does anyone know what kind of sound generating hardware some of   
> games used?  My fave, soundwise,  was probably Defender.  I'd love the
> audio board out of one of those machines!

Williams Electronic Games made "Defender" along with "Sinistar",   
"Robotron" and some others games using the same "series" of game   
technology. I believe that Defender used software generated tones   
programmed as part of the game code, I checked the Sinistar schematics   
last night but they were not complete and only gave the Speech Generator   
and audio mixer details - enter Kevin.....(they're the same as Robotron).

I did check the Williams and Bally Pinball audio generation for that   
period last night, as, it was common to use pinball electronics in Video   

As mentioned early Williams sound was generated in code and fed directly   
into the audio DAC (1408). The speech however used a Texas Instruments?   
55516 CVSD chip ( continious variable slope delta modulator) which was   
essentially a custom speech DAC. Phrases for the CVSD DAC were obtained   
from "phrase" ROMs - TMS6x00? (I can't be more detailed because during   
that period games were developed under a vail of secrecy - IC idents have   
been removed and the schematics rarely gave the original chip   
manufactures name), this may be of use to the AH'er trying to make his   
modular talk! If anyone has any detailed information on this chip or how   
it uses phonetics I'd love to know (apparently the data sheet is not very   

Bally first used  the custom 3 channel analogue IC - "AY-3-8910", I've   
just checked the chip itself and and no manufacture ID is given except   
for the two *large* letters "G.I.", Bally went on to use another "G.I."   
chip - the "AY-3-8912" and speech used the Texas TMS5200 CVSD chip with   
TMS6x00 phrase ROM's (definately). Info anyone?

Bally's speech and sound board was known as "Squalk and Talk" and had   
LPF's and Voltage controlled amplifiers (VCA's) using LM3900 OTA's.

Williams "Defender" series electronics used the 55564 CVSD speech chips,   
which, I believe are loaded in serial format rather than parallel.

Hope that helps


/<c.jones at sni.co.uk> / ...and on the 8th day
/01344 850213 Work   / God made Synthesizers
/01344 850209/291 Fax/ ...and God was called
/01628 602106 Home   /   ' Tom Oberheim '

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