Drawbars & Additive Synthesis
Drawbars are sliders that set the volume of each harmonic component of the tone — nine per manual on console Hammonds. Pull out = louder, push in = silent.
The footage system
Labels come from pipe-organ stops (physical pipe length ↔ pitch):
- 16′ one octave below the fundamental, 8′ the fundamental, 4′ / 2′ / 1′ one, two, three octaves above
- 5⅓′ the quint (2nd harmonic), plus other mixture-style harmonics/subharmonics
Each individual drawbar sounds flute-pure; timbre comes from mixing them — the Hammond is a real-time additive synthesizer you play with your fingertips while performing.^[raw/articles/wikipedia-hammond-organ.md]
Culture
- From 1969 onward the footage numbers were engraved on drawbar ends.
- Settings became a language: 888000000 (16′ + 5⅓′ + 8′ full out) = the classic Jimmy Smith sound.
- Players change settings mid-phrase — something impossible on a pipe organ and central to the Hammond's expressivity.
Related
- tonewheel-generator — where the harmonics come from
- harmonic-percussion — the extra attack component added on B-3/C-3
- hammond-b3 — the flagship using them