Controlling C64 SID Chips
#C64SID #SIDChip #TeensyROM #USBSIDPico #Chiptune #Commodore64 #MusicProduction #Plogue #ChipsynthC64
https://theoasisbbs.com/controlling-c64-sid-chips/?feed_id=4843&_unique_id=689f33915b76d

Another silly Friday I-should-probably-be-getting-more-work-done thought. I was chatting on the forum post about my SID 2.0 idea on the X16 forums (https://www.commanderx16.com/forum/index.php?/topic/4938-my-take-on-a-sid-20-hint-its-the-filter/#comment-23675) and came up with a digitally controlled all analog back-of-the-napkin modern SID design. Details are in the post but in brief:

For each voice:

SSM2131 for Saw, Tri, PWM
a noise source (LSFR or a simple transistor noise circuit perhaps)
SSI2146 quad VCA to build a voltage controlled mixer to mix the 4 oscillators.
AS3310 VADSR for envelope control
9 DAC outputs (1 for pitch - ala V/Oct, 3 for the mixer, 1 for PWM, 4 for ADSR)
2 logic outs for the gate and trigger for the ADSR envelope

You'd build 3 of these and then they would go into some sort of switching/mixer to route them through an SSI2140 filter or not, then mix that together and finally out. 2140 would be controlled by 2 more DAC outputs. I'm not mentioning all the parts here like the op-amps that may be required at various points but I think that might cover it?

That's quite a few parts! And it wouldn't sound anything like a SID - it'd just have similar capability.

I'm gonna stick with the SSI2140 eurorack module and X16 filter card but it was a fun off-topic exercise!

#C64SID #SID #chiptune #AnalogSID #SillyFridayIdeas #Synthesizers