NoteProcessors are a powerful tool for manipulating notes. Each type of NoteProcessor serves a different purpose to adjust values for pfields. They can be used to apply musical effects to a group of notes; some possible uses include humanizing rhythm, added crescendo/decrescendo, reassigning notes to different instruments, applying time curves, and transposition of material.

NoteProcessors can be applied on a per-SoundObject basis. They can also be applied to an entire SoundLayer to affect all SoundObjects on that layer, as well as applied globally to all notes generated in a piece by applying the NoteProcessor to the root PolyObject.