Groove Sound Sensor AV to dB

Hey, For a school's project i have to detect baby's cry to enable a motor. I want to get the dB value from analog but i can't :/

I try to analyse the elec schematics but he is really hard to me I try to make dB value known and see the Analog value but it's again i fail. Because when I increase dB the AV become really variant.

I need your helps guys please !

PS: Sorry for my english, I don't speack english in my country.

Please post a link to the datasheet of the sensor you use.

Also your code so far is helpful.

Do you understand what dB actually means? It is not an absolute value but a ratio of two measurements.

Look at this web page http://en.wikipedia.org/wiki/Decibel

I want to get the dB value from analog

There is no need to convert the value from the A/D into dB if all you are going to use is a threshold value, just use the appropriate number.

Grumpy_Mike:
Do you understand what dB actually means?
It is not an absolute value but a ratio of two measurements.

It makes me grumpy when I hear news reports quoting noise levels in dB when they really mean dBA.

Russell.

Hey guys, Firstly thanks to your fast response, Thanks to you, now i understand why my exp fail ! But I haven't solve my problem :/

I program on Arduino Uno Shield, my audio input is a grove sound from the Starter kit (seeedstudio) http://www.seeedstudio.com/wiki/Grove_-_Sound_Sensor

I actually do many searchs on my problem but if someone can help me (again) how to get this treshhold value with accuracy >:)

Thanks again to your support ^^

PS: Sorry for my english, I don't speack english in my country.

I actually do many searchs on my problem but if someone can help me (again) how to get this treshhold value with accuracy

The only way to do it is to calibrate it.

That is expose it to a sound of the required level and see what number you read from it. Then use that number as your threshold.

The number will be not only dependent on the loudness of the sound but also dependent on the distance your microphone is from the source of the sound.