Per-grain processing applies a different transformation to each grain, producing granular heterogeneity

In granular synthesis, feeding the entire grain stream through one shared effects channel tends to sound flat and one-dimensional. Per-grain processing instead applies an individual transformation to each grain: each grain may pass through its own constant-Q filter with a center frequency and bandwidth randomly selected within user-set limits, with the number of active filters equal to the grain density. Per-grain pitch-shifting, ring modulation and spatial placement can vary grain-by-grain in the same way. The resulting heterogeneity of sound is the signature of truly granular signal processing, and is what distinguishes real granular sound design from simply playing a sample through effects.

Examples

Per-grain bandpass: every grain gets its own random center frequency and bandwidth. Per-grain spatialization: each grain is scattered to an individual point in virtual space (Roads’s granulators since 1988).

Assessment

Explain the difference between processing a whole grain stream through one effect and per-grain processing, and why the latter sounds more characteristically granular.