Distance from a source changes the balance between direct and reverberant sound

Evidence

The effect of these two aspects is shown in Figure 7.28. As one moves away from a source of sound in a space, the level of direct sound reduces but the reverberant sound stays constant. This means that ratio of direct sound to reverberant sound becomes less and so the reverberant sound becomes more dominant. The critical distance, where the reverberant sound dominates, is dependent on both the absorption of the space and the directivity of the source. — David Howard, Jamie Angus, coustics and Psychoacoustics, 2437

This behavior of the reverberant field has two consequences. First, the balance between the direct and reverberant sounds will alter depending on the position of the listener relative to the source. This is due to the fact that the level of the reverberant field is independent of the position of the listener with respect to the source, whereas the direct sound level is dependent on the distance between the listener and the sound source. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1750

Categorization

• DEFINE: Introduces ‘critical distance’ — the point where reverberant sound takes over from direct — a key psychoacoustic concept.
• XREF: Connects to the Soundscape book’s lo-fi/hi-fi distinction, where natural ambient sound vs. humanity-dominated sound forms parallel direct-to-reverberant dominance ideas. — connects to: More reverberation relative to direct sound makes listeners judge a source as farther away. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1525
• SEED: Possible essay angle on ‘where you sit is what you hear’ — the acoustics of position in concert halls, churches, and living rooms.
• corroborated: 2 independent passages support this claim — David Howard, Jamie Angus, coustics and Psychoacoustics, 2437; David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1750