Shepard Riser

How it's made

Source

a Shepard–Risset glissando. Nine sine/triangle/saw partials spaced exactly one octave apart all glide upward on the same exponential (log-frequency) ramp, so the pitch seems to climb forever.

Body

a fixed bell-shaped (Hann) loudness window over log-frequency fades each partial in near the bottom (base ≈ 30 Hz) and out near the top (≈ 15 kHz); a partial wrapping from top to bottom is silent at the jump, so there are no clicks and the spectral envelope never moves, which creates the endless-ascent illusion.

Layers

left and right channels carry the same partials detuned ±4 cents, giving slow beating and width; a pink-noise band rising on the same octave ramp adds air and lift; an optional tremolo accelerates.

Envelope

the whole riser crescendos from about −24 dB to full level along a convex curve, while a low-pass opens from dull to bright; a 0.12 s fade after the last bar ends the render without a click.

Variation

`rng` offsets the starting position of the glide and the partial phases; rise speed, length, base pitch, timbre, noise and pulse depth set the presets from brooding to frantic.

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