I've had this Ukulele for about a year now, I bought it from a neighbour purely because it was really really cheap, I never really got round to doing anything with it, its just hanging on a guitar hook in the dining room, every time I looked at it I thought that needs to go in the bin, and then I was looking at various Youtube videos and was thinking about building one of the WS2812b LED VU meters or something along those lines, most are either using vertical acrylic rigid tube or whatever or Horizontal configurations, I wanted to do something different so I'm thinking sound to Light is music based, play music and the LED's Light up, how could I make something different? and then my eye caught a couple of things which would do a Job, the Ukulele being one, could I do something with that, it's a musical instrument, sound to light on a Ukulele would be quite apt, not only would it pick audio up but also when it was being played it would Light up the LED's too, that would look funky and breathe new life into the Ukulele

I have everything to hand, I would use an Arduino Uno to control the LED's an LM393 Microphone to pick up the sounds, power would be supplied by a 9v battery and on/off switch to complete the circuit,

The 2nd object which caught my eye was a big musical treble clef, this is the thing you see on music sheets at the start of the piece, this would be another candidate for some LED's, will save that for another project sometime

Supplies

WS2812b LED Strip

Arduino Uno or Nano

on/off switch

LM393 Microphone Module

9v Battery and connector

Double Sided tape

Velcro

1mm wire to make the bridging connections between the LED's

Step 1: The Ukulele LED Install

I want the Ukulele to look just like a standard Ukulele from the front so I'm opting for installing the LED's to the back of the perimeter of the main body and then take them all the way up the neck and around the machine heads and back down the neck and body, leaving a gap for the wires.

I cut the LED strip where it left the body and started up the neck, you cut in the middle of the solder pads with scissors, these gaps will have soldered wires to make continuity, when using LED's like the WS2812b's they are addressable Individually and they need to go in the same direction. there is an arrow between each LED ensure this arrow is continuous throughout the length of the LED's, the LED's are also self adhesive which is good, so this part was relatively easy.

All I had to hand was white 1mm wire, this is solid wire and would perfect for this project, I just have to be more careful when making the connections.

To make the connections 5v Signal and Gnd I prepare each piece of wire first, then tin the end's and more importantly I put some solder very carefully onto each pad, it's really easy to bridge 2 pads when doing this, if this should happen, put some more solder onto the tip of the iron and this pulls the bridge off, ideally you need a rounded pointed tip when soldering LED strips, only In my experience of course.

I just took my time and made the connections as neat as possible bearing in mind I want it to look normal when looking at it from the front.

It's now time to sort the electrics out.

Step 2: Electrical Set Up.

Although the Ukulele will probably have the LED's for certainly the near future, I didn't want the installation to be permanent, the LED's are self adhesive, and I will use double sided tape for the Arduino Uno, LM393 and on/off switch and Velcro for the Battery, with these in place on the rear of the Ukulele it's time to make the connections.

From the start of the LED's the direction of the arrow going forward I solder some of the 1mm wire onto the pads, leaving enough wire to reach the Uno, once stripped, the 1mm wire just pushes in nicely into the Uno connectors, I will use the 5v and Gnd pins on the LM393 as a common point for wires from the LED's and Uno.

The LED's wiring is 5v Signal and Gnd at the starting point, at the far end a 5v and Gnd is used to ensure all the LED's get equal power, a loop so to speak.

LED signal is Pin 6 on the Uno, The LM393 has 3 Pins 5v Gnd and Out, the out pin goes to pin A0 on the Uno.

Battery connections are the positive to the centre pin of the switch then either the left or right side depending on which way you want to slide the switch for on, this cable goes to the vin pin on the Uno, the Negative cable goes to one of the Gnd pins on the Uno, the 2nd Gnd pin is to the common ground we are using on the LM393.

Its time to power up and test the LED's, there is a small adjustment screw on the LM393 module, turning this gets the optimum balance for sound to light, there is an issue straight away, not all the LEDS are lighting up but it works, so I check this out, this happens quite often with LED's and finding the culprit LED is a pain, I found the faulty Neopixel, had to change out 9 LED's.

Step 3: Testing and Playing Some Audio and Assumptions

I found a suitable copyright free audio track and set it off, instantly the Ukulede springs into life lighting up the whole room, brilliant to say the least.

Looking at the Ukulele from the front you wouldn't know there was 94 LED's around it, that's the effect that I wanted.

Overall I've enjoyed this build, the faulty LED was a pain to find, it's turned a not so used Ukulele into a funky little sound to light Gizmo.

Hope you enjoyed this Instructable and thanks for looking.