This is the Bleep Drum by Bleep Labs (www.bleeplabs.com) converted to a Eurorack module.
It is a pretty basic adaptation with trigger and CV inputs added to make external control possible in addition to the original pad buttons and pitch knobs.
- Similar output circuitry as original, directly from DAC, 5V P-P (which is a bit lower than common in Eurorack)
- Trigger inputs are eurorack voltage compatible (positive edge trig, >1V)
- Input CVs are averaged together with knob values when plugged in (0-5V internally)
- Power switch so it can be rebooted into noise mode independently of rack
- The PCB layout for the RGB LED I used is wrong so the colors don't line up with the Bleep drum manual, but I don't care :) Also, this has little impact when it is just used as sound module.
- additional blinkenlights =)
The original files and source code from Bleep Labs can be found here: https://github.com/BleepLabs/Bleep-Drum
This module is working with the Bleep Drum MIDI firmware v12. Original Bleep Drum programmed chips should also work (but has not been tested).
The internal drum sequencing in the module works I think - I have no original Bleep Drum to compare with - but I can't seem to get it to record or play back anything at all when the circuit sits on a breadboard (this is also why a clock output is missing). It works fine as a sound source which was the main reason I did this anyway so I'll leave it like this. Also, the C&K switches used for the drum pads turn out to be pretty bad for playing anyway.
Panel notes: I ordered the panel from Ponoko, laser cut and engraved on 1.5mm acrylic, black surface on white core. This gives a quite nice panel, black with engraved white text on it. Not exactly bullet proof but solid enought when the PCB is attached with all jacks and additional support screws. The jacks will hold the panel 10mm above the PCB so use matching 10mm spacer bolts. Using a thicker panel (>2mm) is not recommended since the jack nuts will no longer fit properly.
The module has a standard 10pin Eurorack +/- 12V power connector but it only uses the +12V and should run just fine on any DC power source that provides at least 7-8 volts if used standalone.
...that this module was developed entirely without any involvement from Bleep Labs. Whatever may be wrong with it is entirely my doing. Bleep Labs cannot be expected to answer questions about this module or anything related to it.
The schematics, the PCB and the panel are all licensed cc-by-sa (Creative Commons Attribution-ShareAlike) 4.0.