mastic by daylight noise

The MASTIC panel: black, with water weed in gold dots running down it, and a printed channel across its middle with a black plate sliding in it behind a bar on the spine. PITCH, SPREAD, DRIFT, TONE and ROW across the top, RUN, LAMP and HOLD under the channel, the jacks down both sides and along the foot.

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. Scratch the plate: draw on the black. Hold still while it's moving and it draws a line under you. From the keyboard: the arrow keys move the pin, Enter puts it down. Slide it: take the frame by either end, past the head, as fast or slow as you like, and backwards; or tab to the frame and use the arrow keys. A thumb pushes the black back over a scratch.

What you hear is MASTIC, and round it a small rack: drums, a bass, a room. All made in the page.

example patches

The plate, its motor, the slit and the forty bands are MASTIC's engine as designed, running in your browser; the scratches stay on your plates while this page is open. On the module a plate is a plate: you keep it in a box.

The plate

A sheet of opal plastic under a coat of soft black, in a frame that slides across the panel. Take the coat off with a pin, a needle, a thumbnail, and light comes through.
Left to right is time, foot to top is pitch. A line along the plate is a held note. A slant is a glide. Hatching is a shimmering cluster. A thumb pressed into it is a chord.
A scratch makes no sound until it reaches the head on the spine. The head reads what's over the slit and nothing else.
Plates are cheap and you make them. A thumb pushes the black back over a scratch, never quite clean. Anything flat that lets light through will do: a leaf, lace, a page printed on acetate.
Lift the plate out and the lamp falls on every sensor: all forty sing at once.

Moving it

Your hand: any speed, stop anywhere, go backwards. Stopped, whatever's over the slit holds as a chord. A hand always beats the motor.
RUN: how fast the motor may take it. Fully left it's off and the plate stays where you leave it. Noon, two seconds a pass. Full, a quarter of a second, and you can see it rattle.
PLATE: a CV for where it goes, as fast as RUN lets it. A sequencer here throws it from chord to chord.
BACK: a gate. It flies home through everything on it and sets off again.

The row

PITCH, the big knob, with its V/OCT jack: where the foot of the plate sits. Everything above it follows.
SPREAD, the other big knob, and its jack: how far apart the bands stand. Closed, all forty are nearly one note, beating. Noon, a semitone each. Full, seven octaves.
ROW: a three-way switch. First stop, even steps of pitch. Middle, five notes of a dark row, so anything you scratch sits in key. Last, even steps of Hz: at noon the harmonics of PITCH, and the plate is one note's tone.
DRIFT: each band slides off true on its own slow wander, from a slow beat to a haze.

The sound

Forty sines, one to a sensor. A sloping line hands from sensor to sensor and bends the pitch between them, so a glide is a glide.
TONE, and its jack: pure sines at the bottom. As it rises each one folds into something harder.
HOLD: how long a band rings after its scratch has gone by, from a few milliseconds to several seconds. At full nothing lets go, and the plate builds a wall.
LAMP, and its jack: the light itself. At noon the whole slit is lit. Left of noon it closes to the foot, right of noon to the top, and only what's lit sings: a filter you can see.

What comes out

LEFT and RIGHT: the low bands to one side, the high to the other. LEFT alone carries the whole voice.
NOTE: V/OCT, the strongest line on the plate. Scratch a tune and it plays the rest of your rack.
LIGHT: a CV, how much is getting through.
NOTCH: a gate at every mark along the plate's top edge. Those two sensors don't sing. It's a clock you scratched, as fast as the plate is moving.
WHERE: a CV, where the plate is. Your hand on the frame is a long fader.

Specs

Format

Width: 28 HP
Controls: a plate you scratch and slide, 2 big knobs, 5 knobs, a three-way switch

Inputs

PITCH: V/OCT
SPREAD, TONE: CVs, added to their knobs, 5 V the whole way
LAMP: CV, added to its knob, 5 V from noon to the end
PLATE: CV, 0 to 5 V, end to end
BACK: gate, rising past 1 V

Outputs

LEFT, RIGHT: audio
NOTE: V/OCT
LIGHT: CV, 0 to 8 V
WHERE: CV, 0 to 5 V
NOTCH: gate, 0/5 V