Introduce sound sensors and actuators

Sound sources can come from human, animal, car, and so on . To process sound data, we should capture the sound source from physical to digital form. This happens if we use sensor devices which capture the physical sound source. A simple sound sensor is microphone. This sensor can record any source via microphone.

We use a microphone module which is connected to your IoT board, for instance, Arduino and Raspberry Pi. One of them is Electret Microphone Breakout, https://www.sparkfun.com/products/12758. This is a breakout module which exposes three pin outs: AUD, GND, and VCC. You can see it in the following figure.

Furthermore, we can generate sound using an actuator. A simple sound actuator is passive buzzer. This component can generate simple sounds with limited frequency. You can generate sound by sending on signal pin through analog output or PWM pin. Some manufacturers also provide a breakout module for buzzer. Buzzer actuator form is shown in the following...