Inverse-square law governs direct sound intensity even inside enclosed spaces

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 (#corroborates, via linked claim)

Categorization

• XREF: connects to: Sound pressure amplitude falls off as the inverse of distance from a source; Sound intensity measures energy transfer rate per unit area — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 176; Sound intensity falls off as distance squares only in free field, boundary-free conditions (+6 more)

Broader Connections

• Direct sound intensity falls with the square of distance from the source #corroborates (1.00) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1691
• Reflected sound obeys an inverse square law in addition to surface absorption losses #corroborates (0.82)
• Direct sound governs perceived quality in rooms, not room curves #expands (0.72)