Wanna try to become the new super stylish 2020s drummer?

Simple, easy to build 2 x 14 bars stereo VU meter for representing audio level.

Instead of using a keypad to open your front door or even your safe, why not control the mechanism by a slider that glides through pitches?

This project produces an audible warning with LED buzzer ISD1820 output when KY-037 input signal is over the limit.

This tutorial shows how to detect noise level though the mic in your smartphone.