I want to use my STM32F4 “Black Pill” boards to make a morphing wavetable oscillator. Unfortunately, it’s not turning out to be as easy as I thought it would be. The boards I have don’t have Mozzi library support, and I’m having a very hard time finding any Arduino projects for ‘morphing (and/or) interpolating’ wavetable oscillators just by googling it.
The plan is for the oscillator to be able to read wavetables made in the Waveedit software (tables of 64 - 8 bit waves I think) and to be able to read wavetables loaded to the MCU’s RAM from a flash drive. Similar to the Tabula Rasa project (a free, but not open-source wavetable oscillator).
I’m also willing to do this project with minimal libraries/‘from scratch’, but I still don’t know where to start, unless it’s reading an entire book on DSP (which would require learning linear algebra… turtles all the way down)! I also know relatively little about embedded systems outside of the Arduino environment.
It would actually be quite a boon to learn all of these things in the long term, but before I sign up for college to make this oscillator I was wondering if anyone has done a similar project or can suggest any resources. Thanks in advance!
I’ve been on the look out for kits for a DIY wavetable synth but haven’t found anything yet.
I just ordered a couple of WeAct STM32F411 “Black Pill” boards - the ones with the QSPI Flash attached (It’s @analogoutput 's fault after this post Braids THT in KOSMO format - #166 by analogoutput).
I reckon it would be a good place to start for wavetables, so it’s going to be added to my long list of projects. Unfortunately I don’t have any projects or resources to suggest. I’ve coded up a couple of naive single wave-form oscillators that I’ve used in a couple of projects, and I’d probably start from there when I get 'round to making something. When I get around to doing anything I’ll share it, but I wouldn’t hold my breath…
Cheers
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Another option is the @Sonosus VCDO board…
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Ah crap, maybe I’ll just make a braids then!
I want to use this chip eventually, it’s so cool.
Stumbled across this - I’ve only skimmed it and it looks pretty heavy on the maths
but might be worth checking out for ideas.
https://www.musicdsp.org/en/latest/Synthesis/199-rbj-wavetable-101.html
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Thank you! This is 100% what I’m looking for, and the thing that I just need to buck up and do is learn all this math.
It’s legitimately funny to me in this, and many many other documents I’ve read how the first few pages will be totally understandable and then on page 3 they hit you with the
∞
γ (δ)≡ x(t+δ)−x(t−δ) w(t−t)dt …
Like oh word?
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It makes slightly more sense when formatted correctly
slightly
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Hey all, just wanted to show off some progress I’ve made on the oscillator.
It’s using a Teensy LC but since the rpi2040 is much cheaper, uses a similar mcu, and runs at 133MHZ, i will eventually port this over and adapt the hardware for filtered PWM or possibly external DAC.
Maybe that will open up the possibility for multiple outputs too 
.
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