Additive synthesis, built into an actual instrument. Nine drawbars mix real tonewheel footage ratios — including 16′ (half the fundamental, below it entirely) and 5⅓′ (1.5×, between the 1st and 2nd harmonics) — neither of which the Additive page's integer-harmonic engine can produce. Percussion adds a fast decaying transient, but only on the first key you strike from a fully-released chord — a real Hammond quirk, not a bug, so a re-picked note inside a held chord stays quiet. Key click is the switch-contact pop every real tonewheel organ has. And the Leslie is a simplified two-band (horn/drum) rotary-speaker model: each band's own spinning rate modulates both pitch (Doppler) and loudness (directional radiation) — chorale is slow, tremolo is fast, and switching between them ramps rather than snapping, like a motor spinning up.
Fires once when a chord starts, not on every note inside it — play a held chord, add a note, and you won't hear it re-trigger. Release the whole chord first.
play with your keyboard (a s d f …) or click the keys