Change parameters to build an exact command. Your agent runs it with sb and gets the WAV.
Command
$ sb get JXF4J540ZH@1 -o mech-footstep.wav
How it's made
Source
a multi-tonne mech lowers one leg and plants the foot. Three things make sound: a servo drive that spins up and winds down (a 250–900 Hz gear whine), a steel foot plate striking the ground, and hydraulic dampers venting pressure as the leg takes the load.
Body
the impact is a ground thump (a sine falling 90 → 55 Hz in 0.25 s) plus a noise crack, and the plate and leg ring as inharmonic metal-bar modes (size ≈ 0.55, 0.3–0.8 s). The whine is a sawtooth through a band-pass that follows its pitch; the vent is pink noise through a band-pass sinking from 6.5 to 3 kHz.
Envelope
servo whine rises for 0.22 s before contact and falls away over 0.35 s; the strike is instant with a 0.2–0.55 s thump decay; the hydraulic hiss opens at contact and bleeds off over 0.65 s; a small second clank at +0.17 s is the knee lock settling.
Variation
`rng` shifts the whine pitch, the modal tuning (±3 %) and the strength of the settle clank; `weight` lowers the thump and lengthens the ring, `clank` balances ringing metal against dull ground.
Layers
whine (pre-roll), thump + rumble + crack, metal body, hiss, settle clank; all dry.
Parameters
Parameter
Range
Default
Unit
Controls
weight
0 – 1
0.6
—
Weight
clank
0 – 1
0.5
—
Metal clank
hiss
0 – 1
0.5
—
Hydraulic hiss
servo
0 – 1
0.5
—
Servo whine
pitch
0.7 – 1.4
1
—
Pitch
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.