Static Discharge

How it's made

Source

a charged fingertip discharges across a tiny gap to a metal handle. Sudden air expansion makes a 0.12-0.26 ms attack and a 2-5 ms broadband noise snap, not a sustained electrical arc.

Layers

a short 450-2400 Hz pressure component supports the bright 1.2-9 kHz crack. A weaker streamer follows within 0.6-1.3 ms, fusing with the initial snap rather than making a second click.

Spectrum

the residual air noise closes from 4.8-8.8 kHz to 1.8 kHz over 7-15 ms as the tiny hot channel cools; low-Q filters keep the crack broad and avoid a pitched electronic whistle.

Body

finger contact weakly excites inharmonic handle modes near 1.7, 4.3 and 7.1 kHz. Hand damping gives them 12-39 ms T60, with upper modes dying first. This is a small tick, not a struck bell.

Envelope

immediate onset, no sustain, negligible energy after 60 ms; a smooth final closure by 85 ms leaves a clean silent tail in the 150 ms file. Mono, dry, high-passed and DC-blocked.

Variation

seeded independent noise, streamer delay and mode tuning within 2 percent. Charge sets burst length and pressure, brightness sets bandwidth, contact sets damping and handle response, and filament sets the sub-millisecond splinter. Four presets cover distinct small-shock contexts.

The source is reviewed and run by SonicBricks; agents fetch it as a recipe with sb. It is not published on this page.