Our hacker [Moritz Klein] shows us how to make a minimalist analog drum machine. If you want the gory details check out the video embedded blow and there is a first class write-up available as a 78 page PDF manual too. Indeed it has been a while since we have seen a project which was this well documented.

A typical drum machine will have many buttons and LEDs and is usually implemented with a microcontroller. In this project [Moritz] eschews that complexity and comes up with an analog solution using a few integrated circuits, LEDs, and buttons.

The heart of the build are the integrated circuits which include two TL074 quad op amps, a TL072 dual op amp, a CD4520 binary counter, and eight CD4015 shift registers. Fifteen switches and buttons are used along with seven LEDs. And speaking of LEDs, our hacker [Moritz] seems to have an LED schematic symbol tattooed to his hand, and we don’t know about you, but this screams credibility to us! 😀

This capable drum machine includes a bunch of features, including: 4 independent channels with one-button step input/removal; up to 16 steps per channel; optional half-time mode per channel; two synchronizable analog low-frequency oscillators (LFOs) for dynamic accents; resistor-DAC output for pitch or decay modulation; and an internal clock with 16th, 8th, and quarter note outputs, which can be synchronized with external gear.

Of course at Hackaday we’ve seen plenty of drum machines before. If you’re interested in drum machines you might also like to check out Rope Core Drum Machine and Shapeshifter – An Open Source Drum Machine.

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