expedition: 20 HP, a drone that never comes back the same, by daylight noise

The family

Thirty-seven copies, one to a cell of the Shimmer: the first voice in the middle, its six copies round it, then theirs, and theirs. Each copy sits at a clean ratio to its parent, an octave up or down, a fifth, a fourth or unison, and carries a bend of its own. Its cell is lit the colour of how far it has been bent from the first voice: pale on a new unit, every colour of an oil film on an old one.

PITCH: the first voice, 20 to 400 Hz. Every copy follows its parent, so the family moves together. V/OCT, 1 V an octave.

REFRACT: how far each copy bends from its parent. At zero, an organ on octaves and fifths. Turned up, the copies slip off into beating and clusters, each modulated by its parent; at full, a howl. Copies of copies carry every bend before them, so the outer ring runs away first.

Bloom and drift

BLOOM brings the family in ring by ring, in an order each unit is born with. DRIFT remakes it while it plays: a copy, more often from the outer rings, gets a new bend near its old one, and now and then a new ratio, and glides there. Between remakes the bends breathe slowly, which is what you see moving in the cells.

BLOOM: one copy to all 37, a little brighter as they come in.

DRIFT: from never to about one remake a second.

MUTATE: a trigger at every remake.

SHIMMER: a slow CV, 0 to 8 V, of how bent the sounding copies are, for the rest of a rack to drift with.

OUT L, OUT R: the family in stereo, each copy where its cell is.

What it keeps

IN is always heard through the family: every copy is also a resonator at its own pitch, so whatever comes in rings through it. TAKE is how much of it stays, for good. The strongest partials of IN pull nearby copies onto them, so a unit fed on a voice ends up tuned to it; and while IN is loud it keeps a fragment of a second or two, in a memory of twelve seconds, the oldest overwritten. The ring round the Shimmer brightens while it's keeping.

TAKE: from listening and keeping nothing to a fragment every three seconds. TAKE CV adds to it; a gate there keeps this, now.

SCREAM: the button, or a gate into GATE. A fragment comes back in its own voice, through every copy at once, and every cell flares. Held, it loops; a tap plays it once. The older the fragment, the more often it comes back, and the more bent. With nothing kept, it screams its own last two seconds.

Expeditions

EXPEDITION keeps everything through a power cut: what it has become, its fragments, its count. Each power-up is a new expedition, counted on the readout under the Shimmer, and on the way in the whole family and every fragment are copied once more, a little more bent each time. Two units fed different things drift apart, and after a while no two sound alike. There is no reset.

This page keeps one too. Your first visit was expedition 1 of a unit of your own, and each visit since is the next. The patches that feed it change it for good.

The panel

Twenty HP, every part on the line's staggered grid and mirrored about the middle. The art is a lighthouse: the Shimmer is its lamp, its beams going out through the mist across the panel, its tower standing down the middle on a beach.

The Shimmer and its ring under the name, and under them the readout, counting expeditions.

PITCH and BLOOM, then DRIFT and TAKE, either side of the tower; V/OCT, BLOOM CV, IN and TAKE CV beside them at the edges.

REFRACT, the big knob, in the middle, with REFRACT CV and GATE either side; SCREAM at the foot.

SHIMMER and MUTATE, then OUT L and OUT R, down the edges at the bottom.

Inside

One four-layer board sits 10 mm behind the panel, with the jacks, the knobs, SCREAM's switch and 78 RGB LEDs on its front and everything else on its back. A printed black block between them gives every cell of the Shimmer, its ring and each segment of the readout a chamber of its own. An RP2350 runs the family 46,875 times a second on both its cores, and a small FRAM keeps the unit through every power cut. V/OCT and SHIMMER can be calibrated over USB with a meter.

The EXPEDITION panel twelve expeditions in: the Shimmer's cells lit in oil-film colours, its ring glowing, the readout reading 012, with its knobs on.

Drag to look around. Lift the panel to see the baffle's chambers, lit from the LEDs on the board.

Specs

Format

Width: 20 HP
Depth: about 21 mm behind the panel, to the top of the power header (estimated)
+12 V: about 115 mA with the lights dark, about 260 mA at the LEDs' cap (estimated)
−12 V: about 6 mA (estimated)
+5 V: not used; 10-pin header
Panel: 1.6 mm FR4: 59 bare glass windows, gold through black mask
Controls: 5 knobs and SCREAM's button

I/O

V/OCT: 1 V an octave, −2 to +8 V
IN: audio, ±5 V (±9 V before it clips)
REFRACT CV: ±5 V across REFRACT
BLOOM CV: ±5 V across BLOOM
TAKE CV: ±5 V across TAKE; over 2.5 V, keep this now
GATE: SCREAM while it's high (over about 1.2 V)
OUT L, OUT R: audio, under 6 V peak
SHIMMER: 0 to 8 V, slow
MUTATE: 5 V, 10 ms, at each remake

Engine

Brain: RP2350, both cores, 46.875 kHz, 32-bit float
Memory: 2 Mbit FRAM: the family, the count and 12 s of fragments, saved every second
Light: 78 RGB LEDs behind the windows, their current capped
Firmware: over USB-C or the debug header, on the back