Room Acoustics Calculator Back EN · ZH
Acoustics Calculator

Room Acoustics · Reverberation Time Calculator

Set room dimensions and surface materials to compute RT60 per octave band using Sabine and Eyring formulas. Compare against recommended ranges for halls, classrooms, studios and offices.

Parameters
Presets
Room Dimensions
Length L 10.0 m
Width W 8.0 m
Height H 3.0 m
Surface Materials
Floor
Ceiling
Walls ×4
RT60 500Hz Sabine [s]
RT60 500Hz Eyring [s]
Total absorption A [m²]
Room volume V [m³]
Critical distance rc [m]

Theory

Sabine formula:

$$T_{60} = \frac{0.161 V}{A}, \quad A = \sum S_i \alpha_i$$

Eyring formula:

$$T_{60} = \frac{-0.161 V}{S \ln(1-\bar\alpha)}, \quad \bar\alpha = \frac{A}{S}$$

Critical distance: $r_c = \sqrt{A / (16\pi)}$

V: room volume [m³], S: total surface area [m²], A: total absorption [m² sabin]

Design guidelines: Concert hall 1.5–2.5 s · Classroom 0.4–0.8 s · Recording studio 0.2–0.5 s · Open office 0.3–0.6 s. When comparing with ISO 3382 measurements, use frequency-dependent absorption data from certified test reports.