Build and provenance — please read: This is a DIY build, not a factory unit, fitted with an Antumbra black panel rather than the original Mutable panel. The PCB was fabricated from Émilie Gillet's open-source design files, with SMD components machine-placed by JLCPCB. Through-hole assembly, testing and calibration done by hand.

What it does:

Waves that go up and down, from minute-long cycles to audio rates. A digital asymmetric triangle function generator in the lineage of the Serge DUSG and Buchla 281, followed by two stages of shaping.

Three operating modes: AD envelope, AR envelope, and looping (VC-LFO or VC-DO).

Three frequency ranges: low (2 minutes to 2 Hz), medium (0.125 Hz to 32 Hz), high (8 Hz to 2 kHz). The range widens further by applying an offset on the V/OCT input.

The shaping chain: a wavetable waveshaper provides linear, exponential, logarithmic, sinusoidal or arc-sinusoidal shapes for the A and D segments. A second processor then either applies a 2-pole low-pass filter to smooth the sharp edges, or a rubbery wavefolder that adds kinks and bounces. Both under CV control, along with slope/asymmetry (the A/D time ratio).

What sets the 2018 revision apart — four output modes:

• Different waveshapes — main signal, asymmetric triangle, EOA gate, EOR gate
• Different amplitudes — controllable dispatching of the main signal across the outputs
• Different times — voltage-controlled phase and apex shifting
• Different frequencies — harmonically related variations of the main signal

External clocking and PLL: Tides can use an external clock or a clean audio signal as reference and run at a multiple of it, from 1/16 to 16x — so you can generate subharmonics or harmonics from an incoming oscillator.

Designed from the ground up to run at audio rates with minimal aliasing, with every parameter under voltage control, so it works as a self-contained voice as readily as a modulation source.

Specs: 14 HP · +12V 55mA / -12V 5mA · CV outputs 14-bit at 62.5kHz (31.25kHz in different-frequencies mode) · output levels bipolar ±5V for cyclic signals, unipolar +8V for gates and envelopes · Cortex-M4 ARM processor · firmware updatable over audio