Opus Sounds Directory
Chaos → calm

Traffic glitch → warm strings

Chaos → calm · 2026-10-06

Related guide: How to Add Sound Effects and Music to AI-Generated Videos

Claude Opus 5.5

Mid tempoEnergeticDarkSadCalm
New
Space
CC0

Prompt

A 30-second traffic-glitch-to-strings bed in Db major at 90 BPM, for a city-to-calm story ad. Frame 0 hits a sharp urban accent: a truck air-horn chord, two clashing car horns and a low engine thump. For ten seconds the street gets denser. Idling engines drone, cars pass with Doppler pitch drops and left-to-right pans, horns honk on and off a 16th-note grid, and a distant siren wails closer. A digital glitch layer chops the street into stutters, repeats and pitch-shifted slices, and in the last beat it accelerates from 1/32 to 1/128 repeats. At frame 300 (10.0 s) the whole street, echoes included, stops in a 3 ms fade that ends exactly on the cue. Warm synthetic strings (detuned band-limited saw ensembles with vibrato) rise from silence on the same sample. Over 20 s they build slowly: a dark low Db chord, then a bowed contrabass, then a legato violin melody with portamento, then soft 8th-note viola pulses at 90 BPM, an octave doubling and an opening tone. The progression is Db, Ab/C, Bbm7, Gbmaj7, Db/F, Gb, Absus4, Ab. It swells to a peak and lands on a high Db chord at 26 s that rings to exact silence. Only engine lows, the contrabass and a soft sub swell sit below 120 Hz, all mono.

Metrics

Integrated LUFS
-13.6 LUFS
True peak
-6.9 dBTP
Length
30s · 960,000 samples @ 32000 Hz
Target master
-14 LUFS · peak ≤ -1 dBTP
Checks
Passed

Spectrogram

Spectrogram of Traffic glitch → warm strings, a free transition bed at 30s and 90 BPM

Generated code

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Timing & cues

90 BPM · 30 fps · seed 230300

  • Frame 0: urban hit
  • Frame 300: traffic cuts to strings

Traffic chaos (idling engines with mono lows, Doppler car passes with pan sweeps, clashing additive car horns on a 16th grid, distant wail siren, slapback street echoes) is chopped by a glitch layer (stutters, pitched slices, 32nd dropouts) that accelerates from 1/32 to 1/128 repeats into the cut. The bus is filtered, then gated with a 3 ms fade ending on frame 300. Warm synthetic strings (detuned additive saw ensembles, per-voice vibrato, brightness opening from 650 Hz to 3.6 kHz) build over 20 s through Db, Ab/C, Bbm7, Gbmaj7, Db/F, Gb, Absus4, Ab, Db. Layers enter one by one (contrabass, legato violin line with portamento, viola 8th pulse, octave doubling, sub swell) up to about -10 LUFS short-term, then ring out to exact silence. A sub-0.1 Hz Hann-bump DC trim follows the limiter. WAV download is the full 48 kHz master via /audio/chaos-calm-02/out.wav (R2); the static preview asset stays 32 kHz stereo for the Workers 5 MiB cap.

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