run

it ends somewhere else

20 HP

A run of notes on your clock, the same every time round. Bump it and the difference doubles every step: the run plays on as the first one did, then parts from it and ends somewhere new.

The RUN panel: black, in gold dots a railway from above at night, a single track up from the foot splitting at a set of points into three. Over it a path of bare circuit board: a trunk up the middle from the big NUDGE knob, three long timbers at the points, then three tracks to the top, the middle one straight, the outer two curving out. CLOCK and RUN at the top corners, WHEN and CROWD under them, the FIRST and RUN buttons either side of the points, KEY's jack left of NUDGE and LENGTH's switch with four dots right of it, NUDGE's jack under it, PITCH, STEP and ACCENT down the left, STRAY, FLASH and END down the right. run at the top, daylight noise at the bottom.

Turn a knob: drag it or tap either side of it, roll the wheel over it or use the arrow keys; a double click puts it back. LENGTH clicks from stop to stop the same way; RUN and FIRST are buttons: hold FIRST a second for a new first run. The patches step on by themselves until you touch anything.

A dark techno groove that clocks RUN, and an acid lead on its PITCH, STEP and ACCENT. Listen plays the patch from its top.

example patches

Everything RUN does here is its engine as designed, running in your browser. The groove and the lead are a stand-in rack.

The run

Four small chaotic maps, started from one seed, make the run a step at a time: each step a note or a rest, tied or accented, its interval up or down a scale. Started from the same place, they make the same run every time.

The bump

A bump too small to change a note doubles every step until it does, and from there the run goes its own way. Each run gets a bump of its own, so runs two, three and four end three different ways, every time.

Strangers

The lights

The run climbs the trunk through its opening, crosses the points from the bump to where it parts, and takes a track: straight on if it never parts, out to the side the last run didn't take if it does. The last run's way stays faintly lit.

What comes out

Inside

One board sits 10 mm behind the panel with everything on its front: the jacks, the knobs, LENGTH's switch, the buttons, the 67 LEDs and the whole circuit, the USB-C in a notch in its left edge. Each cell of the run has its own cell in a black printed baffle, lit by its own white LEDs, so the run lights cell by cell up its track. An RP2350 plays the run 4,096 times a second, its four maps in 64-bit floating point.

The RUN panel with a run gone its own way: the trunk and the points lit, the run up the right track, the last run's way faint on the left, its knobs, jacks, LENGTH and the buttons on.

Drag it or use the arrow keys to turn it; click it to take it apart.

Specs

Format

Width
20 HP
Depth
20.8 mm behind the panel
+12 V
about 45 mA dark, 95 mA with a run playing, 190 mA at the most (estimated)
−12 V
about 5 mA (estimated)
+5 V
not used
Controls
a big knob, 2 knobs, a four-way switch, a lit button, a button

I/O

CLOCK
gate, a step on each rise past about 0.9 V; unpatched, nothing moves; safe to ±12 V
RUN
gate, past about 0.9 V: round again at the next step, as the button does
KEY
1 V an octave, −6 to +6 V, to the nearest semitone; a 24-bit converter, calibrated; safe to ±12 V
NUDGE
CV, added to the knob, 5 V the whole way; −6 to +6 V, safe to ±12 V
PITCH
1 V an octave, −5 to +5 V (a note past that folds by octaves), 16-bit, calibrated
STRAY
CV, 0 to 8 V, 1 V each time it's ten times further
Gates
STEP, ACCENT, FLASH: 0/5 V
END
trigger, 5 V for 10 ms

Engine

Brain
RP2350, 4,096 steps a second, its four maps in 64-bit floating point
Runs
8, 16, 32 or 64 steps, each after the first with a bump of its own
Light
67 white LEDs in the run's 32 cells, 128 frames a second
Power cycle
keeps its first run's seed and the calibration; it wakes to run one at the first CLOCK