This is not a perfect emulation as the TB-303 has unique oscillators and filter designs. I tried my best with simple bandlimited oscillators and two cascaded bob~ and focused on modulation behavior instead. As I don't have a 303 at home, I used Propellerheads Rebirth RB-338 to match (or rather guesstimate) settings by ear.
Design based on an analysis of the TB-303 by Robin Whittle, Oscillators by @Maelstorm
I can sounds somehow convincing if:
- you drive it with a sequencer using 1/32 note length with 1/32t silence gap between them. Two notes superposed will trigger the legato. Use velocity >= 100 for accented notes.
- you send it to a distortion unit (Guitarix is perfect for that).
Have fun, any feedback is welcomed!