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
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

Generated code
Loading…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.
More like this
More free chaos → calm on the directory.