Subway Platform

How it's made

Source

an underground platform in a tiled tunnel station. A steady tunnel rumble (brown noise, 28-100 Hz) and a faint ventilation hum (100/200 Hz) underlie everything. One train cycle (arrival, dwell, departure) spans the render and repeats every 30 s in longer renders.

Train

wheel-on-rail roar is pink noise low-passed from ~350 Hz up to 1.5-4 kHz as the train closes in, with a 40-150 Hz rail rumble, a carriage-joint clatter (sparse band-passed ticks) and a saw-wave motor whine that glides with speed (200-800 Hz, filtered dark) while the train moves.

Brake squeal

while the train brakes to a stop, noise through a Q 22 two-partial resonator (1 : 1.52) sings at ~3.5 kHz sliding down to ~1.8 kHz as speed falls, fluttering with a fast drift, then dies at standstill.

Envelope

arrival is a power-law swell (about 0.04 to 0.4 of the cycle) peaking when braking starts, then decaying as the train halts; a dwell leaves only rumble and air; departure accelerates to a lower peak and fades into the tunnel. The low-passed roar also acts as the pressure push of air ahead of the train.

Space

the tiled hall is part of the sound; the train and squeal feed a hall reverb with a long tail, while the rumble stays dry. The train pans from left (arrival) through centre to right (departure).

Variation

`rng` forks decorrelate the left and right beds; macros set train level, squeal, rumble, roar brightness and tile reverb. Presets move between a quiet late-night platform, rush hour and a far-off tunnel.

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