Room Acoustics Calculator
Calculate room resonant frequencies, RT60 reverberation time, and acoustic treatment recommendations from room dimensions.
Room Acoustics Analysis
Room modes are resonant frequencies determined by room dimensions. They cause peaks and nulls in the bass response.
Axial Mode Frequency = Speed of Sound / (2 × Dimension)
Where speed of sound ≈ 1130 ft/s (344 m/s) at room temperature.
Unit conversions:
- 1 foot = 0.3048 meters
- 1 meter = 3.28084 feet
- Speed of sound: 1130 ft/s = 344 m/s
RT60 estimation (Sabine equation — time for sound to decay 60 dB):
RT60 = 0.049 × Volume / Total Absorption
For an untreated room with moderate furnishings:
RT60 ≈ 0.049 × V / (Surface Area × avg absorption coefficient)
Ideal room ratios (to distribute modes evenly):
- Bolt ratio: 1 : 1.28 : 1.54
- IEC ratio: 1 : 1.4 : 1.9
- Avoid cube-shaped rooms (1:1:1) — modes stack up
RT60 targets by use:
- Recording studio (control room): 0.2–0.4 sec
- Home studio: 0.3–0.5 sec
- Listening room: 0.3–0.6 sec
- Lecture room: 0.5–0.8 sec
- Concert hall: 1.5–2.5 sec
Treatment priorities:
- Bass traps in corners (addresses room modes)
- First reflection points (absorption panels)
- Rear wall diffusion or absorption