Introduction: The Musixel BoomBox
The Musixel is a board designed to interpret the frequencies in music or sounds and generate a light-show on up to 64 addressable LEDs. The Musixel has a few modes built-in, one of them is a 'Graphic Equalizer' styled visualizer that is more than just a little cool. In this project it runs an 8x8 matrix for a stunning visual in time with your music.
For this version of the Musixel BoomBox I made a laser cut acrylic box. You can download the cut file below. Don't have a laser cutter, no worries. Some of my buddies have made Musixel BoomBoxes out of cardboard and used hot-glue to put them together, they sound and look great! Take a look at their cardboard box (photo in step 15).
Get creative and have a party!
Step 1: Getting Set Up With Parts & Plastics
To get this project up and going, I assembled the following components.:
The acrylic casing was designed pretty quickly, using some of the tab-hole design that I've perfected on other projects. This style of casing has a structural 'skeleton' as well as a cosmetic cover, so you don't see the tabs fitting through the holes. Used a 1/32" semi-opaque white to act as a diffuser for the LED matrix. They can be a little too bright sometimes.
Tools: To build this, I used a variety of workbench supplies.. Excluding the laser cutter, most folks have these already.
• Soldering Iron & Solder.
• Snips & Wire stripper.
• Lengths of different colored wire (makes it easier).
• Glue gun & glue sticks.
• Double sided tape & Kapton or electrical tape.
No screwdrivers were needed at all in this project.
The plastic used is 1/8" acrylic, and the diffuser is 1/32", or 1/16" whichever you prefer.
Your own "Musixel BoomBox" doesn't have to be identical to this one, any box could work. Here is a Musixel BoomBox Parts to the Musixel BoomBox webpage.
Step 2: Peeling Plastic Parts
If you're making a laser cut housing, it is time to peel the protective layers of paper / or plastic sheeting off the laser cut pieces. It is easier and quicker to do the majority of the peeling all at once. I like to leave the outer protective layers intact until the very end.
One thing to note when it comes to acrylic... It gets dusty & scratched up pretty quickly.
Step 3: Soldering Lengths of Wires to the Parts
To make the build process more streamlined, I soldered lengths of wire in the following way:
Double red and double black wires to the DC barrel jack. This is splitting the +5v DC to both the Musixel and the amplifier.
Blue wires to the momentary button. - This will be connected to the MODE button on the Musixel.
Green, White, and Yellow wires to the sound input, and a separate trio of the same colors to the TRRS board.
Those two sets of three wires join each other as well as the Musixel, using the audio-jack holes on it to connect, and act as a tie-point at the same time.
The TRRS board (Stands for Tip-Ring-Ring-Sleeve) is a 4 conductor possible connection. The Tip is standard for the LEFT channel, Ring 1 is standard for RIGHT, Ring 2 is Mic (unused here), and the sleeve is Ground.
Step 4: Review
This is the complete 'wired up' project. Generally I would have this at the end to so that you can check all you connections, in this case it helps show you where everything gets connected, and how the Musixel board is a junction for power in & audio in being split off. Come back to this step if additional clarity is needed.
Step 5: Lengths of Wire to the Speakers - Glue the Speakers Down
These speakers were marked with a (-) and (+) I used the green wire for (-) and alternate colors for the 2 channels. Because the speakers are attached to the front of the housing, I left enough slack on the wires so that I didn't have to fight with limited clearance during final assembly.
Hot glue bonds to clean acrylic extremely well. Did I overdo the glue? Probably, but that's one of my personal trademarks.
Step 6: Attach the 8x8 Matrix Panel to the Musixel Board
The Musixel has a 3 connection points on the left side of the board. DO (Stands for Data-Out), +5v and GND (Ground). I connected these using color coded wires in the photo above. The only possibly odd thing about these connections is that the DO goes to the DIN. Much simpler when you think of it as a 'Data out goes somewhere... where does it go? Oh of course, to the Data In'
Step 7: The Build So Far..
This is as much soldering as we can do before having to involve the front and back housing panels. The DC in barrel jack, and momentary button are both 'Panel Mounted' meaning they get installed and affixed to the housing / rear panel.
Step 8: Rear Panel
On the left of the first photo above, you can see the DC power jack, and on the right side, the volume knob and momentary button. Having just the right circle cut out for panel mount fittings is an art form. It takes a while to become familiar with what you're cutting, and your laser cutter. Once you know what the tolerances are it's a real breeze.
The groove on the bottom is to allow the audio cable to pass out of the box. I thought about cutting into the wire and soldering it directly, bypassing the TRRS breakout, but the wires inside those audio cables are usually very thin, and too fragile & troublesome to solder.
Here you can see the jack and button ready to be soldered to the rest of the circuit.
Step 9: Mounting the 8x8 Matrix
I build a set-back stand for the matrix. This brings it inside the box, and gives me a reference point for being able to have it centred left to right, as well as top to bottom. The notches above and below fit through the top and bottom structural plastics of the housing. I used some double-sided acrylic tape to hold it in place.
Step 10: The Rest of the Soldering..
Power cables from the DC barrel jack that I soldered at the start go to both the amplifier, as well as the Musixel. Starting to become a little bit of a mess, but that's okay. Color coding the wires makes it really easy to see what's left to solder. The mode button soldered to the Musixel, and finally the speakers get connected to the amplifier. I made sure to keep an eye on the left-right stereo. If its your first time working with speakers, keep in mind that it reverses when you're looking at it from the front. Much like telling the difference between 'my left' and 'your left'..
Step 11: Plug in Audio Cable and Protect.
TRRS is going to be the only "loose" item inside the housing. Because it has bare contact points, I wanted to be sure I didn't create a time bomb that could possibly send +5v to my music player. (Or worse my phone or computer!!) So I used something called Kapton tape. It's like electrical tape, but the adhesive doesn't come loose, it's non conductive, not affected by temperature, and it's very easy to work with. It's what electrical tape would be if electrical tape was awesome.
Also, I made a small knot in the cable that will remain inside the housing. This is to stop stress on the plug / TRRS board if someone yanks on the audio cable.
Step 12: Matrix Mount, and Closing Up the Box.
Needless to say, before you close it up, you want to make sure that everything is working as expected. A bad solder, or defective part is much easier to replace at this point rather than at the end of this step.
Visually double check your connections, and then power up, and send some music in. If all looks and sounds great, keep on going.
The way I designed this housing was to have it built from the inside out. The matrix stand holds the top and bottom structural pieces in place as they are being placed onto the front structural piece. The structural side pieces are slipped into place and then the back gets put into position and gently eased into position.
This design style is tab-hole, where there is just enough tightness on the tabs and holes to mesh, and not fall apart. This entire box may have retaining nuts holding the button and DC jack in place, but the box itself is press-fit, and it stays together extremely well. Not even one screw was needed.
Step 13: All Set, Just the Finishing Touches to Go.
Here it has really come together great. I left the white diffuser off so that you can see the matrix panel recessed and centered inside the box.
The front protective paper is still intact, and I spent a good amount of time pressing along the edges to get a perfect press fit. It is always a great feeling when it all comes together perfectly.
Step 14: White Diffuser and Front Cosmetic Bezel
The front cosmetic panel is affixed to the Musixel BoomBox using double sided acrylic tape. I centered the white diffuser onto the sticky side of the bezel, and then peeled away the rest of the tape release. Then peeling away the protective paper from the front of the box, it sticks perfectly centered in place.
A few strips of double-sided acrylic tape gets applied to the top - bottom - left - and right sides. The associated cosmetic pieces fit right into place, and give the box a great solid sharp black obelisk look. It also makes the box incredibly strong. I am not saying an adult could stand on it... It feels very rigid none the less.
Step 15: Done!!
Thanks for reading, if you have questions or comments I would love to hear from you. Always a pleasure.
