Change parameters to build an exact command. Your agent runs it with sb and gets the WAV.
Command
$ sb get ZN8K2Q6VQH@1 --preset cellos -o tension-string-ostinato.wav
How it's made
Source
a section of bowed strings playing short detached (staccato) notes. Each note is a bow stroke: a stick-slip sawtooth (rich in all harmonics) from three slightly detuned players (±7 cents) plus a 10–30 ms burst of bow-hair noise at the onset.
Body
the instrument body adds broad resonances (≈ 280 Hz air, ≈ 1.1 kHz and ≈ 2.8 kHz wood); a low-pass whose cutoff falls from the bright bow bite to a darker tail across every note gives the spectral movement.
Envelope
~12 ms bow attack, then a decay of 60–260 ms depending on how short the stroke is; a quiet sustained low drone (root an octave down, slow swell) glues the gaps between notes.
Rhythm
eight pulses per bar, accents in a 3+3+2 grouping for drive. Tempo snaps to a whole number of bars inside the loop length, so the ostinato repeats without a seam.
Pitch
two-bar minor phrase on the root (root, octave, minor third, fifth, minor second in bar two) that keeps the tension unresolved; the register shifts the whole figure by semitones.
Variation
`rng` varies each note's tuning (±0.2 %), strength and stereo position slightly.
Parameters
Parameter
Range
Default
Unit
Controls
tempo
80 – 150
120
—
Tempo (BPM)
length
0 – 1
0.35
—
Note length
bite
0 – 1
0.5
—
Bow bite
register
-12 – 12
0
—
Register (semitones)
drone
0 – 1
0.4
—
Low drone
accent
0 – 1
0.6
—
Accent
seed
int
1
—
Variation, reproducible
The source is reviewed and run by SonicBricks; agents fetch it as a recipe with sb. It is not published on this page.