Total energy produced by sound source


I have measurements of the sound intensity produced by a sound source for a given frequency (*). These measurements were taken on on a grid on an imaginary sphere around the source. From these measurements it is clear that the sound intensity is not equal in all directions.

The measurements are calibrated in [tex]DB_{SPL}[/tex].

The problem: how can I get an estimate of the total energy dissipated by the source?

What I did so far is:
-for each point I calculate the area of the sphere that is covered by the point.
-I convert the DB values into intensity values: [tex]I = 10^{DB/10}[/tex].
-multiplying the Intensities in each point with the area of covered by the point
-summing all these numbers.
-to get an absolute intensity value, I multiply this number with 10^-12 (the sound pressure level base for calculating Db values).
-This number should give the number of WATTS. This should be multiplied with the duration the sound source is on.

The questions:
-So, is this correct?
-Is there a quick way to calculate the energy dissipated for example using a simple model for a source?


(*) The source produces more than 1 frequency of course. But let's start off easy.
Go to

This is an online calculator relating sound SPL's, Pascals (Newtons per square meter), and watts per square meter.
Thank you for the reply, but I knew about this site.

The problem is that it just gives a way to calculate Intensity ( = W/M² or J/M²S) from Decibel. It does not give a way to calculate Energy (W*Time) for non-uniform distribution of W in space.

So, that does not help me very much to solve my particular problem. But I agree that is a top site.

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