this document surveys synthesis and processing methods beyond pure additive techniques, organized by category.
builds timbres by filtering and shaping rich oscillator outputs rather than summing sines alone.
common oscillators:
square
triangle
sawtooth
pulse/rectangle
sine wave (as a special case)
pure single-frequency tone, no harmonics
retains shape under linear superposition
common implementations: direct sin()
calls, lookup tables, polynomial approximations
creates complex timbres by modulating one oscillator’s frequency with another at audio rates.
provides broadband or textured content, often as input to filters.
basic signal operations:
addition/subtraction: mix or difference signals (e.g. chorus, phase cancellation)
multiplication/division: envelope shaping, gating, or normalization
convolution: spectral filtering and reverb when using impulse responses
splits audio into short "grains" and reassembles them for creative time and texture manipulation.
sample-based vs. formula synthesis:
traditional sequencers often map as follows:
this high-level model parallels the event-based, hierarchical approach used in advanced synthesis frameworks.