Have you ever listened to a musician play guitar near a campfire? Something about the flickering lights and shadows creates a mysterious romantic ambiance that’s become an icon of American life. Sadly, most of us spend our lives in the cities, and rarely have a chance to experience a fireside serenade… Until now.
In this tutorial, you will make an interactive flame ring that, when placed inside a guitar, will visualize music as it is being played. Based on the volume and variation, it hears, the ring will flicker and shine in exciting patterns. The CampFire Flame is perfect both for students just starting out with guitar, and for street musicians who play at night. It casts a bright, distinct, and colorful projection from within the guitar, and forms melodic shadows when the hand plays strings over the sound hole. Makers can easily make derivative spinoffs of the code controlling the pattern of light the ring emits.
Step 1: Parts, Tools, Supplies
- 3D Printer Filament
- Neopixel 24x Ring
- Adafruit Feather 32u4 Basic Proto
- Battery Packs Lithium Ion Polymer Battery 3.7V 1200mAh
- Mic with Adjustable Gain
- Dremel Idea Builder 3D Printer
- Soldering Iron
- Wood Veneer
- Hot Glue Gun
- CampFire Flame Arduino Sketch
- CampFire Flame Enclosure
Step 2: Circuit Diagram and Code
The circuit is relatively simple, requiring no resistors or other components between the three main devices. I've attached a notated diagram, which will work right out of the box with the included code. As shown in the photo, the mic is attached to the Feather board on the built in breadboard.
Make sure you separate the board by 6 or 7 inches of wire. This will allow easy placement into the 3D printed enclosure described in the next step.
Once the circuit is complete, open the CampFire Flame sketch and upload it to your Arduino. The code is easily customizable; it is based on the Fire2012 example from the FastLED library. Fire2012 is driven by probabilities; on a scale of 1 to 255, you control the probability of different effects on the fire, like sparking, cooling, and flame hight. In the CampFire customization, I have mapped the mic's output to influence this probabilities in various ways. I also added a sparkle effect that is activated once the volume of the guitar is high enough.
All of this is explained in the comments of the code, which also will instruct you on the customizable variables.
Step 3: Print the Enclosure
If you know how to use a 3D printer, building this enclosure should be simple!
Attached is the sketch-up file I used, which includes all three individual components; the enclosure, the faceplate, and the circuit shield. Export from sketch-up into the file type compatible with your 3D printer (.obj and .stl are the most common).
The print uses a simple snap-in mechanism to contain the components. Hot glue the net-pixel ring into the side of the case with 'teeth', and tuck the wires between the grooves. The battery and Feather are placed on the other side of the case.
Once all the components are neatly assembled in the print, snap the top enclosure into place. Then, slide the legs of the shield into the square slots, making sure that the mic slides into the circle in the shield left open for it.
Once you have printed the shield, use any thin paper, sticker, or wood to decorate it and make it match your instrument. Trace a circle around the edge of your material, cut it out, and hot glue it on. I used thin sliced maple.
Step 4: Mount the Flame
Use mounting tape to place the CampFire Flame onto your guitar. Just slide the neo-pixel ring under the strings and press the shielded side against the guitar. Once it is plugged in, the CampFire Flame will automatically start simulating fire based on real time sound! Patting your guitar for a base effect will cause a nice glitter effect. In the dark, this device will form memorizing shadows.
Step 5: Now Your Ready!
Take the camp-fire with you!
Bring light and joy to the dark and forgotten places in the world! Or just get lost in the mesmerizing light show. However you use your CampFire Flame, you will be sure to create an alluring ambiance everywhere you go.