A poor man's version of the legendary Roland TR909 Drum Machine
The PM-909 is basically a 16 step sequencer that mimicks as much as posible the TR909. The circuit can be used to control drum modules from the TR-909 drum machine. It can also be used to control any set of drum modules that accept 5 Volt triggers and CV (control voltages) from 0-5V for the accent input.
Features:
· Open Source
· High / Low Accent (adjustable for each voice individually)
· Flam on all voices (if flam is set to maximal, 32th notes can be played)
· Shuffle on all voices (if shuffle is set to maximal, all even notes are delayed a 32th note)
· Create, play and edit drumtracks consisting of 48 different drum patterns. A drum track can have a length of 224 measures (patterns)
. Pattern mode: create tracks by playing different patterns on the fly
· Save up to 16 drum tracks on an EEPROM
· Internal clock and external clockable (e.g. using LFO or MIDI)
· MIDI in The module can be synced by an external MIDI clock (e.g. a DAW) to play a programmed rhythm
· The module can play a MIDI drumtrack that was programmed in a DAW. (only tested with Ableton Live)
· MIDI out: A drumtrack can be recorded in a DAW. (This is somewhat rudimentary)
· Customizable through simple confirguration file
· Create random rhythm patterns: (some of the random patterns are quite OK )
· Random improvisation on an existing pattern
By default, the firmware and the circuit are configured to control the 11 standard drum sounds that are found in the TR-909. Both firmware and hardware are easily adjusted to control upto 16 different drum modules of any kind, as long as they accept 5 volt triggers and 0-5 volt accent CV. If a higher level of CV is required (for instance, 15 volt CV when using TR-808 modules) the opamp buffers at the CV output should be adjusted to have a gain of 3.