Crystal Hum

How it's made

Source

a glass-like crystal driven continuously by a faint internal energy, so it sustains a hum instead of decaying. Every partial is a steady sine; there is no strike transient.

Body

glass partials at 1 : 2.0 : 2.76 : 4.07 : 5.4 : 7.9 of the fundamental (inharmonic, bar-like), with amplitudes falling roughly 1/n so the tone stays pure and glassy; `brightness` lifts the upper ones.

Beating

a real crystal is slightly asymmetric, so each partial splits into two modes a fraction of a hertz apart (0.15-1.4 Hz, `beating`), panned to opposite sides; this gives the slow pulse and a wide image.

Envelope

each partial swells and fades on its own slow low-frequency cycle (0.125-0.5 Hz, whole periods in the 8 s loop), so the spectrum breathes; `power` sets the depth of the swell and the upper-partial surge.

Shimmer

a very faint narrow band of pink noise around 6-9 times the fundamental, wandering in pitch and level, plus a quiet sparkle partial pair; `shimmer` sets its level.

Variation

`rng` mistunes partials by up to 0.3 % and sets the swell phases and the shimmer wander.

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