Sound Level Measurement using Arduino

Sound Level Measurement

Using sound sensor we detect ambient sound. This board along with the microphone, has a small built-in amplifier (integrated circuit LM386), because only the microphone would not be able to send signal to Arduino. The connection scheme is very clean, composed of only 3 pins: Vcc, GND and S (signal). In the middle of the plate, there is a potentiometer for sensitivity adjustment.

Sound Sensor Module

Sound Sensor
Sound Sensor

The board works with 5V voltage, and the signal pin should be connected preferably to an analog port of Arduino, since the generated signal is variable, and thus we can see the different levels of noise picked up by the microphone.

Circuit Diagram of Sound Level Measurement

Sound Level Measurement Circuit
Sound Level Measurement Circuit

Arduino Code for Sound Level Measurement

// Program: Sound Level Measurement   
int num_Measure = 128 ; // Set the number of measurements   
int pinSignal = A0; // pin connected to pin O module sound sensor   
long Sound_signal;    // Store the value read Sound Sensor   
long sum = 0 ; // Store the total value of n measurements   
long level = 0 ; // Store the average value   

void setup ()  
  pinMode (pinSignal, INPUT); // Set the signal pin as input   
  Serial.begin (9600);  
void loop ()  
  // Performs 128 signal readings   
  for ( int i = 0 ; i <num_Measure; i ++)  
   Sound_signal = analogRead (pinSignal);  
    sum =sum + Sound_signal;  

  level = sum / num_Measure; // Calculate the average value   
  Serial.print("Sound Level: ");
  Serial.println (level);  
  sum = 0 ; // Reset the sum of the measurement values  

Result of Sound Level Measurement

Open Serial monitor and see the result.

Sound Level Measurement Result
Sound Level Measurement Result

5 thoughts on “Sound Level Measurement using Arduino

  1. Hello!

    I am successfully using this sound level sensor in a project of mine.
    I am taking 500 samples and averaging them but I need to multiply the
    digital value output by 500 to get workable sound level numerical values.
    No Idea how you get ouput in 200’s. Can you e-mail the electronics schematic of the sensor?

    Thank you very much.

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