What am I getting from this sound sensor?

Forum 2005-2010 (read only) Hardware Interfacing
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Hello Everyone,
I have searched the forum to see if anyone has come up on this...I am sure it has been brought up before, perhaps I am not searching correctly. Needless to say I am very green in terms of Arduino and such, but I have a sensor kit that I have constructed. It includes several sensors, including this one for 'sound'

http://www.superrobotica.com/S300490.htm
http://www.superrobotica.com/download/Robonova/soundsensor.pdf

Can anyone point me in the right direction as to what exactly I am getting from this? I get values ranging from 0 to 532. How can I use these values, for example, to detect dB levels? I doubt the sensor has the ability to detect frequencies, I think its more just measuring the amount of noise...but should this not be able to be translated to dB?

Apologies for my 'newness' if any of this is dead obvious. I would appreciate any help on how to get a useful value from this. I am concerned with comparing sounds in the ranges found on this site:

Thank you in advance!
Luis

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It most likely contains a simple low pass and an amplifier, as the output of a microphone is hardly above 100mV.

To use it you have to calibrate it, i.e. apply a sound of known intensity, measure the voltage, and correlate them.

Microphones are generally quite linear with respect to mV/Pa.

To get the noise in dB you have to compute the logarithm of the measured (calibrated) value.

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Thank you for the responses. I will report back once I go through what you have suggested.

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