Erica Synths x Hexinverter HexDrums

Erica Synths have resurrected the now‑legendary Hexinverter percussion modules to create a drum machine that’s as immediate and playable as it is individual.

HexDrums is a collaboration between Hexinverter Électronique, a Canadian Eurorack modular company that closed its doors in 2022 due to post‑pandemic supply chain issues, and Erica Synths, who subsequently acquired the rights and continued manufacturing, selling, and supporting some of Hexinverter’s most popular modules.

Amongst those modules were the Mutant Drum series, a collection of x0x‑inspired drum voices that have become the core of this analogue drum machine. There are 10 drum voices comprising two bass drums, a flexible percussion engine called Machine, snare, clap, rimshot, hi‑hat (open and closed), and two sample‑based cymbals. The most obvious equivalence is with the mighty TR‑909. The HexDrums wears the influence proudly, but is not shy about deviating from established norms and treading its own path.

Hex Appeal

The HexDrums is a chunky desktop unit that comes in a lively black‑and‑yellow livery. It offers real‑time control over every drum parameter, individual outputs for all voices, a hands‑on 64‑step sequencer with pattern memory, a song mode, a stereo master compressor and an overdrive circuit. Operation is intuitive, and if you’ve ever used a classic analogue drum machine, you’ll barely need to open the manual.

At 455 x 216 x 91mm, Hexdrums is a solid desktop unit. Its all‑metal casing, black wooden side panels, mechanical cherry keys, and panel‑mounted pots and switches make it feel robustly old‑school. All the inputs and outputs on the rear are on proper grown‑up quarter‑inch jacks and 5‑pin MIDI sockets. In short, the build quality is superb.

The Drums

The first of HexDrums’ two bass drum voices is ideal for the heavy kick drum commonly used in techno, electro and many other electronic music genres. It’s a combination of a triangle core VCO (square or sine wave), a sub‑oscillator, a pitch envelope with variable decay, a pitch control with a range of several octaves and an adjustable click level. The results are very flexible, ranging from soft, short clicky kick drums to long disco toms, typical 909 kicks, and massive gabber techno window‑shakers.

The second bass drum is based on the TR‑808 twin‑T damped sine‑wave oscillator. Unlike the TR‑808, however, you can tune the fundamental frequency to match your song, or high enough to create tom sounds. It has just three controls (excluding level): pitch, decay and tone.

The Machine voice is the most complex of all, capable of a wide variety of percussion, synth voices and special effects. It consists of two synthesis parts, a dual‑oscillator membrane and a noise section. With a variety of envelopes to provide amplitude and pitch variation (one of which can be permanently opened for drone sounds), you can achieve semi‑realistic snares, dark techno rumbles, bass sounds, zaps, blips and noise blasts.

The dedicated snare drum voice uses two bridged‑T sine‑wave oscillators, adding a noise element, two octaves of tonal pitch control, and a resonant filter to create a surprisingly versatile snare. It will emulate 808 snares with ease, and 909 snares up to a point (I couldn’t quite get the ‘snap’ right).

The clap uses a linear feedback shift register to create the noise elements, essentially producing white noise that, when pitched down, becomes more digital‑sounding (like 8‑bit noise). There’s a simulated reverb that doesn’t sound...