tharn

12 HP · freeze

A stereo freeze, caught in the headlights. Sound passes straight through until the headlights come on, from a gate at LIGHTS or a sudden loud jump at the input. Then it stops dead and the last moment is held, a smeared still, shaking as much as TREMBLE says, for as long as FEAR says. Then it bolts: back to the present at once, or sprinting through everything it missed until it catches up.

The THARN panel: an old car coming head on at night in gold dots on black, its two round lamps the module's two headlights in chrome holders, tharn on its roof and FEAR on its grille, the wet road's reflections running down between the jacks. White labels for the knobs FEAR, TREMBLE, BOLT and STARTLE and the jacks FROZEN, RUN, LIGHTS, IN L, IN R, FEAR CV, OUT L and OUT R.

Turn a knob: drag it, roll the wheel over it or use the arrow keys; a double click puts it back.

The rack round it is made in the page, in stereo all through: headphones help.

example patches

The sound and the headlights here are THARN's own engine: the module's firmware, ported to the page and checked against it sample for sample. The drums, the bass, the pad and the voice it freezes are stand-ins for the rest of a rack.

Caught

IN L and IN R go straight to OUT L and OUT R, untouched, until something sets it off: a rising edge at LIGHTS or, with STARTLE up, a sudden jump at the input. Then the dry sound is gone in 4 ms and the moment is held in its place.

The held moment isn't a loop. THARN averages the spectrum of the frames round the trigger, about a tenth of a second before it and 40 ms after, so a hit that set it off is in the picture. It plays that back as a steady sound at the moment's level, every frequency at its own pitch: a chord becomes a drone, a snare a hiss in its own colour, a word one held vowel. Each side is frozen on its own. It's been listening all along, so the still is there the instant it's caught.

Fear

Startle

A fast envelope of the input against a slow one, both above 200 Hz so a long sub can't hide a crack. When the fast one jumps over the slow one by more than STARTLE's threshold, and past 0.4 V, it freezes itself and the headlights flash.

Tremble

Bolt

When FEAR runs out it bolts, and RUN fires. BOLT says how.

The panel

Twelve HP, every part on the line's staggered grid and mirrored about the middle. The art is a photograph of an old car coming head on at night in the rain, in gold dots on black, the wet road's reflections running down between the jacks as short gold dashes. Its round lamps are the module's headlights: cold white LEDs in chrome holders either side of FEAR, dark while it passes, glaring while it's frozen, brighter with the freeze's level.

Inside

The THARN panel frozen, its headlights glaring, with its knobs on.

Drag to look around. Lift the panel: the headlights' holders go with it, and their LEDs stay standing on the board. One RP2350 does it all, its two cores sharing the freeze.

Specs

Format

Width
12 HP
Depth
about 21 mm behind the panel, its power header included
+12 V
about 115 mA passing through, 160 mA at the most (the headlights glaring, FROZEN high)
−12 V
about 10 mA
+5 V
not used; 10-pin header
Panel
1.6 mm FR4: ENIG gold through black mask, white labels
Controls
4 knobs, FEAR's big; no switches

I/O

IN L, IN R
audio, ±5 V with room to ±9; 100 k. IN R normalled to IN L
LIGHTS
gate, rising past about 1.2 V; 100 k
FEAR CV
±5 V, a tenth of FEAR a volt; 100 k
OUT L, OUT R
±5 V, 1 k
FROZEN
gate, 0 or 5 V, 1 k
RUN
trigger, 5 V for 10 ms, 1 k

Engine

Brain
RP2350, both cores, 46.875 kHz, 32-bit float
Converters
PCM1808 in, PCM5102A out, on one I2S clock
Freeze
4096-point frames, a quarter-frame hop, both sides at once
Memory
8 MB PSRAM: 4 s of stereo it missed, for the sprint
Headlights
two 5 mm cold white LEDs in chrome holders, 20 mA each at full
Firmware
over USB-C or the debug header, on the back

Nothing's for sale yet.

THARN is designed and its firmware builds. Nothing has been made, so the numbers here are the design's and the engine's, not measurements, and there's no date.