Decibels in noise sensor

Hi,
I'm using Octopus Analog Noise Sound Sensor Detection Module (it's like a normal sound sensor without the potentiometer) in Arduino UNO programming with Arduino IDE. I want to get the value in decibels, but i can only get the analog value and I haven't been able to find any libraries... I also tried different programs where an operation is performed to convert the value, but the resulting decibels differ a lot from what it's supposed to be. If someone knows what can I do to get the db value from this sensor I would be very grateful.
Thanks in advance,

Mariona

marionabrusii:
Hi,
I'm using Octopus Analog Noise Sound Sensor Detection Module (it's like a normal sound sensor without the potentiometer) in Arduino UNO programming with Arduino IDE. I want to get the value in decibels, but i can only get the analog value and I haven't been able to find any libraries... I also tried different programs where an operation is performed to convert the value, but the resulting decibels differ a lot from what it's supposed to be. If someone knows what can I do to get the db value from this sensor I would be very grateful.
Thanks in advance,

Mariona

Like this article proposed, I would suggest that you using a phone app to measure the sound level and use it in parallel with the arduino, then plot dB level from the app vs the ADC read from the arduino to generate either an array table or if there exist a formula relating the two.

hope that helps...Arduino Sound Level Meter - Measure Sound/Noise Level in dB with Microphone and Arduino

how do you calibrate? what is your reference?

Sherzaad, thanks! I already saw this project, but as I'm new using Arduino and programming I thought that maybe there would be an "easier" way to do it, as getting the decibel value is a small part of my final high scool project I'm currenly working on.

Gcjr, this is the sensor used. I bought it because at first I wanted to use it with the BBC micro:bit (getting the db value), but now I'm using arduino. There's no much information of it...

https://www.elecfreaks.com/learn-en/microbitOctopus/sensor/octopus_ef04081.html#

If it's not possible to get the value in decibels from this sensor, could you give me some advice on which sensor could I use?

Thank you!

It’s always possible to “get decibels” from a linear sound amplitude measurement. I’m assuming you have already checked Google and Wikipaedia to learn about decibels, since this is after all, an educational project? Then you see that it is just a mathematical relationship. There is no “easy” way to do this, apart from the suggestions about manual calibration with another device. How could there be, unless you are just buying a professional sound meter off the shelf?

Usually, with a final project, the school is grading you largely on the initiative and resourcefulness that you demonstrate. As described, you definitely don’t need any library for this. You just need to research and understand the problem, translate it into some simple code that only implements a very simple logarithmic equation.

OR..

If you know they are the wrong values.. This must mean you know what the correct values should be.

Use a non-liner mapper function. Put in a bunch of value pairs.

Number I got 1 | Actual Decibel level 1
Number I got 2 | Actual Decibel level 2
Number I got 3 | Actual Decibel level 3
Number I got 4 | Actual Decibel level 4

Probably don't need all that many to get a good enough fit.

Then all you need to do is the map thing.

Decibel = decibelMapper.map(reading); And you're done.

Non-liner mapper library is in your IDE. Search in library manager for LC_baseTools.

-jim lee