Electric Car Pass

How it's made

Source

a low-speed electric car, with a continuous external warning speaker and rubber on asphalt. The speaker uses a 430-650 Hz fundamental with 1.5, 2 and 3 times partials, not combustion pulses.

Body

tyre hiss occupies 450-5500 Hz above a subdued 90-650 Hz rolling bed; a quiet electric drive adds 190 and 380 Hz components. Broad filters avoid sharp resonances and hard high-frequency fizz.

Motion

a straight 3-8 m/s trajectory at 2-6 m clearance uses retarded emission position, inverse distance gain, air absorption and Doppler factor 343/(343+radial velocity). Axles are 2.6 m apart.

Envelope

smooth 180 ms entry, closest approach near 1.3 s, then a soft departure to zero at 2.95 s. Front-facing warning sound dims behind the car; rear tyres linger slightly after the warning peak.

Modulation

warning partials breathe gently at 2.1 Hz with 0.2% pitch wander; tyre contact strength fluctuates independently by 8%. All sources share the trajectory and remain dry, with no reverb.

Variation

seeded phase, 0.6% speaker tuning offset and independent tyre streams. Presets distinguish a slow warning-led pass, brisk tyre-led rolling, a muffled distant pass and a lower two-tone speaker.

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