Arduino MEGA was used for the drum machine and Arduino UNO for the synth module with a MIDI input. Both are enclosed in a “groovebox”.

Two outputs (one for the drum machine and one for the synth module) through PWM, 8 bit resolution, 31372,55 Hz sample rate.

The drum machine has 3 sounds (kick,snare,hihat) that can be andjusted:

Kick (it’s a function of an enveloped and modulated sinus):

-initial frequency(the frequency from which the sine sweeps down to the basic freq.)
-basic frequency (the tone)
-length (release)

Snare (it’s a function combining an enveloped and modulated sinus and noise):
-initial freq.
-basic freq.
-tone length(release)
-noise length(release)

hihat (it’s a sample):
-frequency(pitch)
-length(release)

I have to thank the authors of Auduino. My project started from it and here is the result.
Documentation (only in Slovene, sorry) and source code are available on my web page, you can find them under Projects.

I am a musician and compose and produce music for movies, short films, documentaries and theater plays. The drum machine and synth module was my diploma thesis at the Faculty of computer science at the University of Ljubljana (Slovenia).

This post was submitted by Mitja.

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