Sound sensor, Voice Sensors at affordable cost - Xbotics
This component is ideally suited to adding dual tone multi-frequency (DTMF) decoding to your project. This detection module interprets the incoming tone and produces a coded output that can be connected to all manner of microcontrollers.
Can detect the intensity of the sound environment, use note: the sound sensor can identify the presence of sound (according to the principle of vibration) or a particular frequency of sound does not recognize the volume of the sound. Sensitivity adjustable digital potentiometer to adjust (blue)