This sound detector is based off the ISD1820, which is a multiple-message record/playback device. It can offers true single-chip voice recording, no-volatile storage, and playback capability for 8 to 20 seconds. The board is loaded with a sample which is 3.2k with a the total 20secs for the recorder. This module is very easy use offering direct control by the push button on board or by any microcontroller such as Arduino.