Sound grain is regular modulation, opposed to isolated transients

Evidence

Similarly, grain is a special type of internal fluctuation, one with a regular modulatory effect. It is accordingly contrasted with transients, which are isolated or irregular fluctuations. Grain gives texture; it roughens up the surface of the sound and its effects consist of tremolo (amplitude modulation) or vibrato (frequency modulation). — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 466

Categorization

• DEFINE: Defines grain as regular internal modulation (tremolo/vibrato) set against irregular transients.
• XREF: Links to the tactile-auditory convergence theme (the ‘tactile word’ observations elsewhere in the book). — connects to: Sound mass is predominant bandwidth while grain is regular internal fluctuation — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 465; A sound’s mass is its predominant bandwidth in the spectrum — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 465; Percussion excitation is a short impulse rather than a sustained tone
• corroborated: 2 independent passages support this claim — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 466

Broader Connections

• Sound mass is predominant bandwidth while grain is regular internal fluctuation #expands (0.85) — Schafer, Murray R, The Soundscape- Our Sonic Environment…, 465