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Digital control analog synth? Answered

Hi all! I have an idea buzzing round my head and I could really do with some guidance. I'd like to implement digital control over an analog synth so I could have presets saved on a microcontroller. The synth in question is Serge modular. All the info on various modules can be found on the link below. Ultimately I'd like to be able to save and recall knob and switch settings, not patching. I would like this to be at the highest resolution possible, so no MIDI. Ideally 16 or 14 bit resolution. I'm a beginner in this, although I do know how to solder, but I don't have the underlying technical knowledge. So, how doable is this? What do I need to consider? Has anyone done something similar? Thanks! https://www.cgs.synth.net



5 months ago

Yeah, wow. Wow. What they said...

If you built one from scratch with a pre-made PCB, it might be possible (with small daughter boards) to mount digital POTs right on the PCB. That might simplify things, somewhat. But that depends on how the POTs are wired from the board. Given the large # of POTs and the panel organisation, they generally don't seem to be mounted directly on the PCB, like modern guitar amps.

Regardless, that's a lot of digital POTs. And a communication bus. I don't even want to think about servo control of physical POTs...(yeah, it's been done, so it's possible). Good luck.

you could probably use SPI for control, possibly with an Arduino or similar as an intermediary manager, and digital pots to provide analog pot replacements for the synth's adjustments (which themselves are usually pots of one sort or another) . For the analog synths' switches (say between triangular, square, saw tooth and sine wave drivers, or various switchable modes, you could use digitally addressable, analog multiplexers to drive relays.

Probably not a beginners' project, but very "doable", although as Caitlinsdad said, it might get costly. (in part that depends on what you have in your parts drawers and your skills) . Many of the first "digital synths" weren't much more than that. They simply used midi as a control vector...when external control was offered, that is.

It's doable but in the end probably really expensive. Look at automated audio mixing consoles for sound recording. The banks of faders, knobs and switches are all motorized. Some kind of microcontroller or computer needs to read all the positions (rotary encoders for trimpots and faders, switches) and then can recall them by driving the tiny motors in each component. And with analog synths, it's a whole bunch of knobs and switches, so essentially count on building a control panel to replace the current one and starting about $20 per encoder pot/switch. Good luck.