Total energy produced by sound source

Click For Summary

Discussion Overview

The discussion revolves around estimating the total energy dissipated by a sound source based on measurements of sound intensity taken from various points on a spherical grid around the source. The focus is on the methodology for calculating energy from non-uniform sound intensity distributions, particularly in the context of sound pressure levels measured in dB.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Dieter outlines a method for estimating total energy by calculating the intensity at various points, converting dB values to intensity, and summing these values multiplied by the area covered.
  • Some participants suggest using online calculators to relate sound pressure levels to intensity, but there is a concern that these do not address energy calculations for non-uniform distributions.
  • A participant references a site discussing the angular distribution of sound sources and proposes a polar coordinate equation for pressure distribution, indicating the need for knowledge of angular distribution to apply it effectively.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correctness of Dieter's method or the best approach to calculate energy dissipation. There are competing views on the utility of online calculators and the necessity of understanding angular distribution.

Contextual Notes

There are limitations regarding the assumptions made in the calculations, particularly concerning the uniformity of sound intensity and the angular distribution of the sound source. The discussion does not resolve these uncertainties.

Who May Find This Useful

This discussion may be useful for individuals interested in acoustics, sound engineering, or those working with sound intensity measurements and energy calculations in non-uniform distributions.

dvderels
Messages
2
Reaction score
0
Hello,

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?

Regards,
Dieter




(*) The source produces more than 1 frequency of course. But let's start off easy.
 
Physics news on Phys.org
Bob S said:
Go to http://www.sengpielaudio.com/calculator-soundlevel.htm

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 www.sengpielaudio.com is a top site.
 

Similar threads

Undergrad Summing and averaging RMS pressure (amplitude) of sound waves
  • · Replies 2 ·
Replies
2
Views
3K
Graduate Sound wave intensity (dB) and sound processing
  • · Replies 3 ·
Replies
3
Views
2K
High School What sound frequencies can pass through a hole in a wall?
  • · Replies 31 ·
2
Replies
31
Views
5K
Undergrad Relationship between frequency and power for sound?
  • · Replies 11 ·
Replies
11
Views
6K
Undergrad Sound power, amplitude, frequency, and decibels
  • · Replies 5 ·
Replies
5
Views
2K
High School Sound Intensity doubles if number of noise sources double?
  • · Replies 7 ·
Replies
7
Views
2K
Undergrad Distance from Source to Reach 180/170 dB Intensity Level
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad Sound Loudness vs Pitch Misconception
  • · Replies 9 ·
Replies
9
Views
4K
Graduate Relaxation times of molecules during sound propagation
  • · Replies 3 ·
Replies
3
Views
3K
Undergrad Understanding a sound spectrum analyzer output
  • · Replies 10 ·
Replies
10
Views
9K