Jun 17, 2014

Back in Black - a DIY raspberry pi Boombox: Wire it Up - LEDs

The LEDs for the BinB Boombox are powered by the Sparkfun Spectrum Shield on top of an Arduino.

Spectrum Shield

I needed more +V and GND connections than were available. I used a cut-down piece of Adafruit perma-proto board and created a +V and a GND rail by soldering on female headers. I stuck this in the prototyping area of the Spectrum Shield with double-sided tape. Audio input from the Raspberry Pi is at the top of this picture, where the thumb is.

All of the LED effects are triggered from the Raspberry Pi with a remote control press. When GPIO 24 is set HIGH, the LEDs are on; when set LOW, they are off. GPIO 24 is connected to pin 10 on the Arduino.

From Arduino Pin
NeopixelPin1  (Left as you face the boombox) 8
pi_toggle 10
CS1 (#3) 2
WR (#5) 7
DATA (#7) 6
+5V (#12) 5V
GND (#11) GND

From CS1 in the table on, the connections are from the Sure 0832 LED Matrix. 

Sure 0832 LED Matrix

I used Sugru to attach the Sure Matrix and the VFD to the acrylic frame.

The proto-board below the VFD is for the rotary encoder. The rotary encoder is connected to the Raspberry Pi, so:

 Rotary Encoder wired to Adafruit Perma-Proto Board

Don't forget to add a 470 Ohm Resistor to the DIN (data in) line of the NeoPixels per the NeoPixel Uber Guide.

 NeoPixel 12 Ring - Two Needed

Remember back on the Make the Frame page, I said to keep the circles cut out from the Test Strip? Now we'll use them to cover the hole in the mounted NeoPixel Rings and block out the inside of the boombox.

NeoPixel Ring with scrap acrylic circle glued on as light baffle

The VFD pinouts and connection to the Raspberry Pi were detailed in my earlier post on the Day & Night Sampler.

Final Steps:
  • Screw Speakers into Frame
    • I spray-painted white nylon screws black
  • Solder the Class D Amp with supplied Potentiometer
    • Run 3.5mm cable Out from Spectrum Shield
    • Attach Speaker Wires and adjust Pot
  • Secure Raspberry Pi, Arduino, Amp, Power Distribution Board, USB Hub
    • Use Double-Sided Tape, E6000 or Hot Glue as appropriate
  • Run Cables from USB Hub to power Raspberry Pi & Arduino
  • Plug in a 12V Wall Wart (3A or higher) to the DC In Jack and Press the Push-Button switch
    • LED should light up
    • After about 1 minute, the Raspberry Pi should be ready to play music 
...And cable ties - lots and lots of cable ties.
There's a slightly changed layout for the Remote on this version of the boombox.

Make sure the LEDs are switched on by pressing the Toggle (Back) button.

With the volume turned up past 50%, you should be rewarded with something like this:

No soundtrack on this video. Feel free to hum along with "Back in Black" by AC/DC and Rock Out (in the privacy of your own home)!


  1. Way cool. thanks for the tutorial. i want to do a similar setup and i think this will be a great starting point.

  2. Thanks! When you're done, post a link back. I'm always interested in how people put their own special spin on a thing.