Fat Controller
This is a MIDI to CV converter that I built for my modular system. I've also used the same basic design and PCB in my DrumBox and 3031. The basic idea is a PIC-based precision MIDI to CV converter with multiple outputs and lots of software features.
Perhaps my favourite feature is the ability to drive each of the oscillators in a monophonic patch from different pitch CVs, each with independent portamento time, pitch bend range and octave offset.
Note that this Fat Controller has no connection with the Frostwave Fat Controller Analog Sequencer. The name similarity is just coincidence. Of course the original Fat Controller comes from Thomas The Tank Engine stories, first appearing in 1945.
Feature overview
- I/O: MIDI In, MIDI Thru, 3x Gate, 15x CVs
- CV output range -7.5V to 7.5V (15 Octaves) with better than 2 cent accuracy
- Controls: 4 push buttons, 8x2 character ASCII display
- 4 basic modes:
- 1 MIDI channel, monophonic with up to 3 pitch CVs, each with independent portamento time, pitch bend range, octave offset; 3 gates: note on, note off, inverted gate
- 2 independent MIDI channels, each monophonic; first channel has 2 gates: note on, note off
- 3 independent MIDI channels, each monophonic
- 1 MIDI channel, 3 note polyphonic
- Responds to full 14-bit pitch bend control (pitch bend range from 0 to 127 semitones)
- Responds to velocity (full scale amount from 30mV to 7.50V)
- Various portamento modes: Slide on legato note off only, slide on legato note on only, slide on legato note on and off, always slide
- Portamento times from 40ms to 50s
- Octave offset from -7 to +7 octaves
- Gate re-trigger mode: always or non-legato
- Gate on note off with gate time from 10ms to 50s
- 2 software LFOs with parameters as follows:
- Period: 10ms to 50s
- Shape: Sine, Triangle, Saw Down, Saw Up, Square, Random
- Sync to MIDI clock: 1/64, 1/32, 1/16, 1/8, 3/16, 1/4, 5/16, 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4, 13/16, 7/8, 15/16, 1,4/3, 3/2, 5/3, 2, 7/3, 5/2, 8/3, 3, 4, 8, 16, 32, 64
- Amount: 30mV to 7.50V
- 2 software ADSR envelopes with parameters as follows:
- Trigger source selectable from any of the gate outputs
- Attack time: 0ms to 50s
- Attack level: -7.5V to 7.5V
- Decay time: 0ms to 50s
- Sustain level: -7.5V to 7.5V
- Release time: 0ms to 50s
- Each one of the CV outputs can be directly controlled from: Pitch bend, Aftertouch or any Continuous Controller; has 'learn' mode to assign next used CC; control range full scale amount from -7.50V to 7.50V
- Every configuration parameter controllable via MIDI on a separate control channel
Feature to-do list
(These features may or may not ever happen .. it really depends if I get a need for any of them!)
- Finish 'standard' features:
- Basic modes 2,3,4 are not done yet
- The software LFOs are not done yet
- Lin/Log switch for envelopes
- Microtonal scales
- Allow use of continuous controller pairs for higher resolution control of CVs
- Polyphonic aftertouch
- Multiple configuration memories (currently only a single configuration can be saved)
- Note priority selectable from Newest, Lowest, Highest (currently note priority is always Newest)
More ..