Synthesizer construction

The synthesizer consists (as a lot of other modular analog synthesizers) of a keyboard cabinet and several module cabinets.

The keyboard cabinet contains the keyboard itself, the power supply (from the book Formant Pro MSS 2000 by H. J. Helmstedt), keyboard scanning circuits (guardians), the polyphonic multiplexer, the digital synthesizer bus and a DAC for the first voice (GATE and CV). More DACs will follow, a digital sequencer eventually.
I used 12mm birch plywood for the keyboard cabinet which was not very practical. It is too smooth and the (rather big) keyboard cabinet is quite instable.

The module cabinets are made from 18mm birch multiplex (sides) and 36mm (top and bottom), all stained in mahogany. This looks better in my opinion and is far more hard and stable, but is also a very heavy solution (look at the bent work disk).
The keyboard and the module cabinets are connected via 25 pol. SUB-D - cable (4 wires used, +15V, GND, -15V, CV1).

The circuits are built on Eurocards (Photo / etch). The front panels consist of 2mm white coated aluminium with inkjet printed transparencies stuck on them.

Update 11.01.2005: This keyboard unit is not in use anymore. Please see Simple MIDI Keyboard

Please send questions or remarks to:
Carsten Toensmann