envelopmental sound

envelopmental sound

[in‚vel·əp‚ment·əl ′sau̇nd]
(acoustics)
The portion of the room impulse response consisting of sound that arrives at a listener's location between 20 and 150 milliseconds after the first direct sound, and which has been reflected against walls and ceilings relatively few times.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.