Glass on Glass Scrape

How it's made

Source

two dry glass surfaces sliding under pressure; 1.2–9 kHz noise models asperity friction.

Squeal

friction locks into two bending modes near 2.2 and 3.6 kHz; pressure bends their pitch by up to 13 percent, with irregular 8–17 Hz wander and a weaker noise skirt around each mode.

Body

repeated contact excites inharmonic glass modes at ratios 1, 1.59, 2.31 and 3.43, with 70–230 ms decay; the second surface is detuned 1.3 percent and slightly more damped.

Chatter

rounded 30–95 Hz stick-slip pulses modulate friction and modal excitation, with irregular pulse depth and rate; no isolated full-band impact or fracture is included.

Envelope

contact builds in 25–80 ms, swells unevenly during the stroke, then slips free over 100 ms; a 240 ms ringing release ends smoothly, followed by silence. Default length is 1.5 s.

Variation

seeded mode tuning and independent friction noise; stroke, pressure, size, chatter and grit distinguish thin-edge squeal, broad panes, heavy judder and light sliding contact.

Space

dry mono contact recording; high-pass removes handling rumble, low-pass limits ultrasonic fizz.

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