Sound intensity falls off as distance squares only in free field, boundary-free conditions

Evidence

Equation 6.1 shows that the intensity of the direct sound reduces as the square of the distance from the source, in the same way as a sound in free space. This has important consequences for listening to sound in real spaces. — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1691 (#qualifies, via linked claim)

The sound field in small listening rooms is not diffuse, statistical acoustics do not apply, and there is no critical distance, as classically defined. — Toole, Floyd E, Sound reproduction- the acoustics and…, 1312 (#expands, via linked claim)

Categorization

• XREF: connects to: Sound pressure amplitude falls off as the inverse of distance from a source; Direct sound intensity falls with the square of distance from the source — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1691; Inverse-square law governs direct sound intensity even inside enclosed spaces (+3 more)

Broader Connections

• Direct sound intensity falls with the square of distance from the source #qualifies (0.95) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1691
• Inverse-square law governs direct sound intensity even inside enclosed spaces #contradicts (0.95)
• Statistical acoustics and classical critical distance do not apply in small rooms #expands (0.72) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1312