The Sabine formula assumes diffuse sound that real rectangular rooms rarely produce

Evidence

The diffusion principle is an idealization that is never perfectly attained. Some rooms are of a shape that discourages diffusion of the sound, such as a rectangular room with flat walls. The sound may not have time to randomize and become diffuse. The corrections are especially important for very absorbent surfaces, where a large fraction of the sound energy is removed at each bounce. (The exponential does not apply if too much is lost at each bounce). Many improvements to Sabine’s formula have been made over the years to correct for these effects, but the Sabine formula remains in use by the acoustical profession, with awareness of its weaknesses. — Eric J. Heller, Why You Hear What You Hear- An…, 2491

Categorization

Category: Definitional Content

Related

• Rectangular rooms fail to randomize sound directions, violating Sabine theory (similarity 0.88)
• Sabine’s formula persists despite relying on an unattainable diffusion ideal (similarity 0.88)
• Sabine’s reverberation formula founded architectural acoustics but fails for high absorption (similarity 0.88)
• Diffuse-field equations fail in geometrically extreme rooms (similarity 0.87)
• No reverberation-time formula has universal applicability across rooms (similarity 0.86)
• Flat rectangular rooms do not diffuse sound; slight wall curvature does (similarity 0.86)
• Sabine’s 1898 formula made reverberation time the dominant auditorium design parameter (similarity 0.84)
• Sabine experimentally verified exponential sound decay in a reverberant room (similarity 0.84)
• Room sound homogeneous decay holds for typical rooms but can be engineered away (similarity 0.84)
• True diffuse sound fields cannot form in small absorptive listening rooms (similarity 0.83)
• Perfect diffusion is an unattainable ideal in real rooms (similarity 0.83)
• Wavefield synthesis fails unless the room is completely anechoic (similarity 0.83)
• Sabine’s formula launched the science of architectural acoustics (similarity 0.83)
• Room absorption determines the steady-state level of reverberant sound (similarity 0.83)
• The Sabine equation works well when absorption coefficients stay under 0.3 (similarity 0.83)

Broader Connections

• Rectangular rooms fail to randomize sound directions, violating Sabine theory #corroborates (1.00) — Eric J. Heller, Why You Hear What You Hear- An…, 2511
• True diffuse sound fields cannot form in small absorptive listening rooms #corroborates (0.85) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1256
• Diffuse-field equations fail in geometrically extreme rooms #expands (0.85) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1772
• The diffuse field assumption underpins room acoustics predictions but fails at low frequencies #qualifies (0.80) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1774
• Statistical acoustics and classical critical distance do not apply in small rooms #complicates (0.80) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1312
• The Sabine equation works well when absorption coefficients stay under 0.3 #qualifies (0.80) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 2861
• Sabine’s reverberation formula founded architectural acoustics but fails for high absorption #qualifies (0.75) — David M. Howard, Jamie Angus, Acoustics and Psychoacoustics, 1863
• No reverberation-time formula has universal applicability across rooms #expands (0.70) — Toole, Floyd E, Sound reproduction- the acoustics and…, 1249