Introduction: Bring Your Music to Light! With LED Color Organ

Brighten up your favorite tunes with colored flashing LEDs! Ultra bright 5mm LEDs, red, blue, and yellow, respond to bass, middle, and treble frequencies for a dazzling audio/ visual show.

Watch it in action here!

If you want to build your own LED Color Organ there is a kit with a customized PCB, already labeled with all component placements.

Finally, check out the Jameco Workshop for full instructional video and helpful tips for the build.


Step 1: ICs U1 and U2

Take note of the orientation of the ICs and IC sockets by looking at the notch and matching the notch of the IC to the notch of the PCB.

Step 2: Diodes D1, D2, D3

The correct configuration of the diodes is shown below.  Pay attention to the stripe on one end of the diode indicating the cathode end.

Step 3: Transistors Q1, Q2, Q3

Polarities of the Bipolar Junction Transistors (BJTs) are extremely important. Here, we use the 2N3904, 3-pin package. Match the component to the symbol in the image above.

Step 4: Resistor Color Code (Non-Polarized)

R1, R2, R3, R16, R17: 1kΩ (Brown, Black, Red)
R4, R5, R6: 560k1kΩ (Green, Blue, Yellow)
R7, R8, R9: 6801kΩ (Blue, Gray, Brown)
R10, R11, R12: 39k1kΩ (Orange, White, Orange)
R13, R14, R15, R27, R28: 100k1kΩ (Brown, Black, Yellow)  
R20, R21: 1601kΩ (Brown, Blue, Brown)
R18, R19: 4701kΩ (Yellow, Violet, Brown)
R22: 1M1kΩ (Brown, Black, Green)
R23: 47k1kΩ (Yellow, Violet, Orange)
R24, R25, R26: 20k1kΩ (Red, Black, Orange)

Step 5: Capacitors

C1 through C7, C15 non-polarized capacitors.
C1, C2 0.0022µF
C3, C4: 0.01µF
C5, C6: 0.047µF
C7, C15: 0.1µF
C8 through C14: These electrolytic are polarized with the negative side (shorter lead) indicated by a strip on one side, see image.
C8, C9, C10: 2.2µF
C11: 2.2µF
C12, C14: 4.7µ6µF
C13: 22µF

Step 6: LEDs

D4, D5, D6, D7: Yellow (represents the Treble)

D8, D9, D10, D11: Red (represents the Mids)
D12, D13, D14, D15: Blue (represents the Bass)

Be sure to have the cathode end (shorter lead) facing the side with the flat edge. See image.

Step 7: Audio Jack and Power Jack U4, U5

There is only one way to insert each of these components into the board, so just be sure to apply enough solder to ensure a good connection with each tab.