Introduction: Cardboard Box Bluetooth Speaker
Skill level: Beginner
Build time: 30 minutes
Projected cost: ~$10 (depending on what you have on hand)
In this instructable you'll reuse some old speakers, install them in a cardboard box and connect them to a Bluetooth-enabled audio amplifying card. A decent Bluetooth speaker has never been this simple or cheap to build!
Step 1: Project Background
So let's start off with a little history on this project. I had a JBL Bluetooth speaker at home which my little siblings always used to play music on and one day the charging port broke. Rendered useless, they came to me asking me to buy them a new one. Since these things aren't cheap and I just graduated from college I obviously couldn't afford that. But after looking at my collection of electronics and old gadgets I realized I could build a half decent one that would work fine and wouldn't cost me much to build.
Step 2: Gather Components and Materials
This project is very straightforward and took me only 30 minutes to complete.
What you'll need:
Sturdy cardboard box (actually works quite well, resonates nicely if it's stiff enough)
Set of working speakers (mine were a set of 30W 6.5" Pioneer car speakers)
Speaker wire (thicker and has less resistance than regular wire)
Audio amp card - eBay is a good source, search for one with a TDA7492P chip and Bluetooth module. Costs less than $10. You can also get one of these with an aux port for more connection options. This is probably the only part if this project which you won't already have lying around at home.
Power adapter - my audio card can accept 8-25V, if you use a 12V adapter make sure it can output at least 1A so your speakers won't be underpowered.
Scissors or knife for cutting holes in the box.
Pen and ruler for measuring and marking locations to cut.
Tip: Make sure you hook up your electronics and test the setup before you install everything!
Step 3: Cut Holes and Ports in the Box
Next you will need to trace the size of your speakers onto the side of the box. Think about the orientation that you would like for your speakers later, my box was a little low and I wanted to set it on the floor so I turned it on its side and made the speakers face upwards.
I took a bowl that was a but smaller than my speakers and traced around that once I decided on and marked the positions for the speaker cutouts. Then I cut out the holes with a knife. (Looking at the pictures you'll see I went even smaller in order to give myself more mounting surface)
The side holes were done the same way to make the sound a bit fuller (I'm not an audio engineer but it seems to help). For the power cord I just pierced the side of the box with a small screwdriver.
Step 4: Installing Components
In my case I inserted the speakers from the outside and just taped them to the box. You could use hot glue or any other method but I wanted it to be easy and simple. Reconnect all wires and tape or fasten the loose components to the side or bottom of the box. Try not to totally cover the amplifier card in order to allow it to dissipate the heat that it will create while pumping out your favorite tunes. I created a simple stress relief for the power cable so it wouldn't get torn out of the box by accident. Just wind a bit of tape around the cable and stick it to the wall from the inside so when pulled it gets tight and won't allow the cable to slip.
Check the system to make sure it still is all connected and nothing got unplugged by accident. You can now close up the box and cheers! you have just completed your very own Bluetooth speaker:)
Step 5: Finishing Tips
I painted my speaker black, silver and white just to make it look less like a cardboard box but you could add stickers or a layer of newspaper for a retro effect, let your creativity take over and have fun while doing it!
Please vote for my project in the contests where it is submitted, and if anyone builds this or one similar please post pictures in the comments below! Enjoy!