The sound chip of the Amstrad CPC464

Is this: AY-3-8912


http://www.ym2149.com/ay8910.pdf


Later addition: there is at least one mistake in this post. The AY-3-8912 has D to A converter as seen on block diagram of datasheet. But it seems it is much different concept to what we mean nowadays. Manual states that output of the sound chip is from sub audible to supersonic (eg 150KHz). So does this mean that the D to A is fed by a clock of say 2MHz?

Also production of tones is produced by division of square waves  beginning from a high clock frequency.


So it is really the same idea as the amazing Solina String Ensemble, Farfisa, EKO organs etc which all have division of square pulses to create the raw material for musical notes.


So in fact it is analog but with software control like the amazing Italian EKO organs.


Or perhaps even like TB-303 or Rolland Juno-6 or Siel DK70. Of Cource these as the EKO organs etc use analog filters or ain't her analog envelop signal processing etc.


Later addition. The TB-303 has VCO oscilltor.


But they all sound great.


No nasty digital to analog (bliakh) converters.


Even the ZX Spectrum BEEP command in BASIC sounds great which just a square pulse or whatever. Electrons moving back and forth.





More on Amstrad sound:


Music and Sound on your Amstrad - Ian Sinclair - Melbourne House