AkustykaToPL
Practical guide

RT60 reverberation time explained

RT60 describes the time for sound level to decay by 60 dB in an idealised decay. In practice, T20 or T30 is often measured and extrapolated.

Key principle

Do not optimise one number at the expense of the full spectrum and room purpose.

Step-by-step process

  1. Define the room purpose.
  2. Record dimensions and hard surfaces.
  3. Run a baseline estimate.
  4. Introduce a minimal treatment variant.
  5. Measure, compare and refine.

Decision example

If mid-band RT60 is high but bass remains uneven, more thin panels may improve speech without solving boom. The next step is mode and position analysis.

Open calculatorMethodology

Example

Example: a 4.2 × 3.4 × 2.6 m room with hard walls and partial panel coverage. Change one parameter at a time and compare saved variants.

Limitations

The result is a first-order model. Real reflections depend on geometry, furniture, gaps, mounting and the positions of the source and microphone.

FAQ

Does this replace a measurement?

No. It helps plan an initial variant and budget, but final decisions should be verified with an impulse-response measurement.

Are more panels always better?

No. One-sided absorption can leave bass problems unresolved and make the upper range too dry.

Where is data stored?

Only in this browser until you export a file or delete local data.

Next step

Read the methodology · Treatment plan step by step · Compare variants