FM Metallic Drone

How it's made

Source

a fictional continuously driven metal/glass transducer, represented by three sine FM pairs. Carrier ratios 1, 1.618 and 3.73; modulator ratios 1.414, 2.713 and 2.236 produce unequal sidebands.

Body

the first two pairs form the cold metal body; a quieter third pair adds a glass edge. A sine at 0.501 of the base anchors the field; a very faint 1.8 kHz noise band suggests surface friction.

Modulation

phase modulation implements sine FM without frequency clipping. Index 1.1–5.6 evolves on independent 7–40 s cycles with smooth random wander, redistributing energy among sidebands.

Envelope

1.2 s soft startup, sustained breathing of 20–40 percent and 1.5 s release; no strikes. Carrier micro-drift stays below 0.18 percent; upper layers breathe independently of the anchor.

Spectrum

base 90–260 Hz, low cut at 45 Hz, two gentle low-pass stages at 4.2–6.2 kHz; no feedback resonances or distortion. Maximum significant sidebands remain well below the 24 kHz Nyquist limit.

Variation

seeded phases, slow index wander and independent surface noise; stereo uses separated metal pairs and a moving edge, retaining a centred anchor. No room reverberation is baked in.

Presets

deep dormant core, sparse glass interface, dense active lattice and slowly breathing relic change register, FM depth, motion, edge balance and stereo width together.

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