AVRSynth is a monophonic "virtual analog" synth based,
originally, on the Atmel AT90S8535 microcontroller and was designed
Ziembicki. His aim was to check to see if a simple micro
could be used for sound synthesis purposes. And the result?
The AT90S8535 managed to do all the tasks: front panel switches
and pots services, receiving and processing MIDI messages, and
synthesis architecture is simple:-
two DCO's, a DCF, and a DCA. There is also an LFO and an AR/ASR
Since this initial design was made we have taken over the project and updated the hardware to take the
ATMEGA16 as the AT90S8535 is no longer a production item.
AVRSynth was also released as a full unit in a small desktop case (Mk1) and with a new panel design (Mk2)
Panel components on the the Mk 1 are hard-wired to the main board while the Mk 2 unit employs a Carrier Board to eliminate hand-wiring to the front panel providing for a quicker and easier build.
Source code for the AVRSynth is available (written in Assembler) for those wishing to add new features or experiment with software synthesis.