How to Use KY-034: Examples, Pinouts, and Specs

The KY-034 is a sound sensor module designed to detect sound levels and convert them into an analog voltage output. It is equipped with a microphone and supporting circuitry to amplify and process sound signals. This module is widely used in projects requiring sound detection, such as sound-activated switches, noise level monitoring, and audio-based automation systems. Its compact design and ease of use make it a popular choice for hobbyists and professionals alike.

• Sound-activated lighting or devices
• Noise level monitoring systems
• Audio-based security systems
• Voice-activated projects
• Environmental sound analysis

The KY-034 sound sensor module has the following key technical specifications:

The KY-034 module has three pins, as described in the table below:

1. Power the Module: Connect the VCC pin to a 3.3V or 5V power source and the GND pin to the ground of your circuit.
2. Connect the Output: Connect the OUT pin to an analog input pin of your microcontroller (e.g., Arduino).
3. Adjust Sensitivity: Use the onboard potentiometer to adjust the sensitivity of the sound detection. Turning the potentiometer clockwise increases sensitivity, while turning it counterclockwise decreases it.
4. Read the Output: The OUT pin provides an analog voltage that corresponds to the detected sound level. Higher sound levels result in higher output voltages.

• Noise Interference: The KY-034 is sensitive to ambient noise. Ensure that the module is placed in an environment where unwanted noise is minimized.
• Power Supply: Use a stable power supply to avoid fluctuations in the output signal.
• Sensitivity Adjustment: Fine-tune the potentiometer to achieve the desired sensitivity for your application.
• Microphone Orientation: Ensure the microphone is oriented toward the sound source for optimal detection.

Below is an example of how to use the KY-034 with an Arduino UNO to read sound levels and display the values in the Serial Monitor.

// KY-034 Sound Sensor Example with Arduino UNO
// Reads the analog output of the KY-034 and displays the sound level in the Serial Monitor.

const int soundSensorPin = A0; // KY-034 OUT pin connected to Arduino analog pin A0

void setup() {
  Serial.begin(9600); // Initialize Serial Monitor at 9600 baud rate
  pinMode(soundSensorPin, INPUT); // Set the sound sensor pin as input
}

void loop() {
  int soundLevel = analogRead(soundSensorPin); // Read the analog value from the sensor
  Serial.print("Sound Level: "); // Print label to Serial Monitor
  Serial.println(soundLevel);   // Print the sound level value
  delay(500); // Wait for 500ms before the next reading
}

• The analogRead() function returns a value between 0 and 1023, corresponding to the voltage on the OUT pin.
• You can use the Serial Plotter in the Arduino IDE to visualize sound level changes in real time.

1. No Output Signal

   • Cause: Incorrect wiring or loose connections.
   • Solution: Double-check the connections to ensure the VCC, GND, and OUT pins are properly connected.

2. Inconsistent Readings

   • Cause: Unstable power supply or excessive noise in the environment.
   • Solution: Use a regulated power supply and minimize ambient noise.

3. Low Sensitivity

   • Cause: Potentiometer not adjusted correctly.
   • Solution: Turn the potentiometer clockwise to increase sensitivity.

4. Output Always High or Low

   • Cause: Faulty module or incorrect orientation of the microphone.
   • Solution: Replace the module if faulty, and ensure the microphone is facing the sound source.

Q: Can the KY-034 detect specific frequencies of sound?
A: No, the KY-034 is designed to detect general sound levels and does not differentiate between specific frequencies.

Q: Can I use the KY-034 with a 3.3V microcontroller?
A: Yes, the KY-034 operates at both 3.3V and 5V, making it compatible with 3.3V microcontrollers like the ESP32.

Q: How do I know if the module is working?
A: You can test the module by clapping near the microphone and observing changes in the analog output voltage.

Q: Can I use the KY-034 for voice recognition?
A: No, the KY-034 is not suitable for voice recognition as it only detects sound levels and does not process audio signals.