Multimode filter with character switches, based on the Bastl Cinnamon
Schräg (also know as Schraeg, for the umlaut-deficient) is effectively a repackaged Bastl Cinnamon:
- Multimode filter with independent outputs (2-pole LP, 2-pole HP, 1-pole BP)
- V/oct input
- Self-resonates for use as a sine oscillator
- Input with an attenuator and 5x gain switch
- Two character switches for altering the resonance tracking
- All-SMD construction in a DIY-friendly format, with 0603 handsoldering footprints, all components on the back of the circuit board
- Built mostly using standard and easily-available components
with a few modifications:
- larger 8HP form factor, allowing for a big juicy cutoff knob
- Voltage control over resonance, through an attenuverter
- FM input through an attenuverter, which works as a pitch fine-tune control with nothing patched
- Larger character and gain switches
- A bi-directional power connector, with polyfuses
- An Interactive BOM to aid in part placement
The additional functionality is achieved with a minimum of extra components, thanks to the two unused VCA cells in the original design.
The schematic, board layout and graphics are released under a cc-by-sa license. Bastl Instruments generously gave their permission for me to release my rework of their module. They’re a cool company. Go check out their work!
https://github.com/barnabywalters/Schraeg
submitted Jan 18th 2021, 13:39 by
