View License

Download apps, toolboxes, and other File Exchange content using Add-On Explorer in MATLAB.

» Watch video

Highlights from
Sound Level Meter

4.1 | 10 ratings Rate this file 52 Downloads (last 30 days) File Size: 1.84 MB File ID: #9603 Version: 1.0
image thumbnail

Sound Level Meter



12 Jan 2006 (Updated )

Implements real-time spectrum analyzer and displays decibel level.

| Watch this File

File Information

This tutorial/demo presents the design of a sound level meter in Matlab. The Data Acquisition Toolbox is used to implement a real-time spectrum analyzer. The decibel meter is implemented in the frequency domain using Parseval's relation.

Documentation is provided in the included PDF.

Further information is available at:


Real Time Octave Analysis inspired this file.

This file inspired Noise Measurement With Matlab Implementation.

Required Products Data Acquisition Toolbox
MATLAB release MATLAB 7.1.0 (R14SP3)
Tags for This File   Please login to tag files.
Please login to add a comment or rating.
Comments and Ratings (18)
20 Sep 2016 micpro

micpro (view profile)

When I import another wav file, I did not get dBA result. Can anyone help me please?

Comment only
04 Aug 2016 Julien Weber

28 Aug 2014 anuj

anuj (view profile)

i am unable to run the file. I am getting errors like not enough input arguments

Comment only
14 Jul 2014 ngan

ngan (view profile)

02 Feb 2012 Chi

Chi (view profile)

how to run the file ?

Comment only
25 Jun 2011 Joachim

20 Feb 2010 sourabh

when i run the SLM following errors come plz someone help me to remove them i am new to matlab
??? Invalid handle object.

Error in ==> updateDisplay at 23

Error in TimerFcn: '@updateDisplay'.
Invalid handle object.>>

Comment only
27 Dec 2009 umut arioz

Those codes were helped me in my works. But I want to use them in simulink. But of course, some functions dont work with embeddeb functions in simulink. for example "find". did you do before to carry this program to simulink or Can you offer me some way instead of using "find" ? thanks

25 Mar 2009 Brian

Brian (view profile)

Cheers, great help as tutorial on real-time data aqusuisition

28 Oct 2008 sameer ahamed

It is a nice model of Sound Level Meter. My observation is: In the code, A-weighting is performed in frequency domain (i.e. multiplication in frequency domain). I feel like, if the A-weighting is in time domain (filtering, of input signal which is sampled at variable sampling frequency), the computation of fft can be saved.

Comment only
05 Jun 2008 nguyen quy

I want to see the source coding

Comment only
28 Feb 2008 Shufang Dong

Generally ok, but with miscellaneous errors need to be correct such as the A-weighting filter should be applied to pressure square rather than pressure, and the last formula of RMS of filtered pressure should not be divided by delta t.

18 May 2007 smekfm gtlo

i am to try this software

05 Jan 2007 Steven Kolak

MATLAB supports audio acquisition using the Data Acquisition Toolbox.

View the MATLAB sound resource page for additional demos, downloadable code examples, and user stories:

Comment only
05 Dec 2006 kesho hassan

it is goog

18 Oct 2006 radwa magdy

23 Sep 2006 Piyorot Khongchuay


Comment only
18 Jan 2006 Rupesh Sancheti

the information given about the products using matlab is excellent

Contact us