Friends bragging lately about the quality of the sound of their drum machines?

Tell them you can make sounds lower fidelity than they can.

LUNCHBEAT is a 1-bit groovebox, making impossibly-dirty digital sounds, with a built-in step sequencer. While we await a proper DIY kit, it’s an ideal learning project: it’s nice and simple, has a low part count, everything you need as far as specs is available free to create your own, and it’s a good way to work out the basics of digital sound and sequencing.

And, really, if you need more than one bit to make music, what kind of musician are you? Go minimal.


Minimalistic groovemachine !
– 4 channels with 1 bit realtime generated sounds
– kickdrum, snare, hihat and bass
– 8 step sequencer
– MCU atmega328p@16MHz
– 8 LEDs with 74595 shift register
– 3 bit R2R resistor ladder DAC
– LM358 opamp as output buffer
– buttons, pots, resistors, wires, protoboard
– programmed in C
– compiled with avr-gcc
– uploaded with avrdude
sources released –

And it’s all hackable, especially if you know Arduino:

ISP6pin – hacker’s gate to unit’s microcontroller. Tweak the sound algorithms. Tweak the sequencer. Change unit’s purpose completely. Use the fact that Lunchbeat is the same thing as Arduino with 6 buttons, 5 pots, 8 LEDs on SPI shift register and 3-bit digital to analog converter. You can run Arduino sketches on it. From here it is up to you and your fantasy.


And you should be able to build this with your lunch money. I hope you do have lunch money and lunchtime, I mean, after plugging a cable from the back of your PC speaker to the front last week.