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

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

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  
  delay(100);
}  

Result of Sound Level Measurement

Open Serial monitor and see the result.