Acoustical Calculator

Acoustical Calculator Graphic for Measuring Echo/Reverberation Level in Room
Acoustical Calculator Graphic

Purpose: Our Acoustical Calculator helps you determine the reverberation time and/or “echo level” of your room.

Solution: Input your dimensions and material information below and we will provide you 1) the Reverberation Time, 2) Available options to Mitigate Reverberation, and 3) How Much is needed to achieve Ideal Acoustics in your space.

More Info: We have also written extensively on How this Acoustical Calculator works as well as which Room Surfaces affect Absorption Coefficients the most. In Brief, to calculate reverberation values, we use Sabin’s Formula, developed by Professor Sabin of Harvard University to measure acoustical performance. The equation states: RT60=.05*V/Sa, where RT60 is the reverberation time, or more specifically, the time it takes for the reverberation to dissipate below a certain level. 0.05 is a constant derived by Professor Sabin, V is the Volume of the space, and Sa is the Acoustical Absorption of the space, which is simply the Surface Area multiplied by the Acoustical Coefficient of each surface. For more information, check out our blog here.


Step 1. Enter All Numbers Below in Feet

Step 1 Results: Below are the Surface Areas and Volume of the Room.

Step 2. Enter the material type for the Wall, Ceiling, and Floor below.

Note: Smooth, glossy, and dense surfaces reflect sound back inward, causing echo and reverberation, while plush, soft surfaces are acoustically absorptive. Select the material type of each surface to find the acoustic coefficient of that surface. A list of all surfaces by acoustical coefficient is here.

Step 2 Results: Below is the Acoustical Absorption area of each surface. This is calculated in units of "Sabins"

The reverberation time is calculated via Sabins Formula, using the pre-determined Acoustical Absorption Area and Volumes calculated above.

Step 3. Determine Acoustical Treatments necessary to achieve your desired reverberation time.

The reverberation time you need in your space depends on what you're trying to accomplish. If you're trying to record high-quality audio, you'll want the reverberation to be as low as possible. However, general uses for assembly, office space, and residential are typically fine in the 0.5-0.7 second range. A brief chart is below:

0.3 seconds: Dead Space

0.5 seconds: Ideal for Conversation

0.7 seconds: Acceptable Acoustics

1.2 seconds: Begin to lose speech intelligibility

1.5 seconds: Reverberation is classified as an "echo"


So you know how much absorption you need to acoustically treat your room. Now What? Check out our Sound Absorption products to select which options fit your budget and aesthetics. Not sure which product is right for you? Use our Product Selector Tool to help choose the acoustical treatment that best fits your needs.