DIMI-A cheat sheet

Categories: DIMI-A

Only piece of original documentation that remains of DIMI-A is an A4 cheat sheet describing the instruction set of the instrument. Original version has a few mistakes in it, these are fixed on this revised version.

Band pass filter frequencies are calculated according of the components on PCBs. In real life they are slightly off because of the component tolerances. Frequencies are compromises aimed to give a peak on every A note on octaves 1-8. The original sheet lists center frequencies roughly on note F on octaves 2-9, but in reality they are not tuned that high.

The sheet expects A4 (MIDI note 69) to be tuned to 440Hz. Octaves will then match standard MIDI octave numbering. I usually pull out this chart from UNSW for reference.

Here is the original sheet from 1970: