Mech Footstep

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.

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