Reverberant sound level stays constant with listener position while direct sound fades with distance

Evidence

The direct sound and early reflections follow the inverse square law, with the addition of absorption effects in the case of early reflections, and so their amplitude varies with position. However, the reverberant part of the sound largely remains constant with the position of the listener in the room. This is not due to the sound waves behaving differently from normal waves; instead it is due to the fact that the reverberant sound waves arrive at the listener from all directions. — David Howard, Jamie Angus, coustics and Psychoacoustics, 1786

Categorization

• DEFINE: Explains the key acoustical concept of the reverberant field and why it behaves uniformly in space.
• XREF: Connects to soundscape/psychoacoustics work on sources versus field, and to how directionality structures auditory perception. — connects to: Reverberant sound level stays constant with listener position because reflections arrive from all directions; Moving away from a source makes reverberant sound progressively dominate while it stays constant; Room absorption determines the steady-state level of reverberant sound — David Howard, Jamie Angus, coustics and Psychoacoustics, 1781 (+5 more)
• corroborated: 2 independent passages support this claim — David Howard, Jamie Angus, coustics and Psychoacoustics, 1786

Broader Connections

• A critical distance exists where reverberant sound begins to dominate the direct field #expands (0.95)
• Room absorption determines the steady-state level of reverberant sound #expands (0.85) — David Howard, Jamie Angus, coustics and Psychoacoustics, 1781
• Large path-length variation causes poor direct-to-reverberant ratio and feedback #expands (0.82)
• Sound pressure amplitude falls off as the inverse of distance from a source #corroborates (0.80)
• Low absorber rooms raise overall sound level because reverberant energy persists longer #expands (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1756
• Reverberant rooms make loudspeaker directivity important for sound quality #qualifies (0.70) — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 474