The design of the project includes connecting 4 LEDs in the +12V from the computer. The LEDs are soldered to a 2-position switch that will connect to TIP31.
The intensity transmitted by the P2 connector is taken by TIP31 which causes the LEDs to blink with the music. A small black box is used to install everything inside. Six holes were made where 4 in the top for LEDs and the switcher and cables on one hoe in each side. To arrange the components easier inside the box, the LEDs were soldered with one small cable connecting each one.
Circuit LED Blinking
This simple project aims to build a circuit that can make the LEDs blink with the sound that comes out from the P2 connector. Shown in the video is the LED blinking in action.
The 3 pins on the P2 connector consist of left channel, right channel, and the ground pin being the bigger. The ground from TIP31 must be connected on the other pin from the switcher. If there is any signal coming from the P2 connector, the LEDs will blink or will always be ON if it is in another direction.