Introduction: Suitcase Stereo (Now With Battery, Solar, and Bluetooth)
This is a story about how I made a suitcase into a stereo, because I wanted to.
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Step 1: Materials
A near comprehensive list of materials needed:
- pair of speakers (mine were 3" inches in diameter)
- Lepai 2020a+ amplifier
- Dremel w/ sanding and cutting bits
- stereo mini male to stereo mini male cord
I found the suitcase on Craigslist for about $20. It's an old British suitcase from around the 1920s era, made of vulcanized fiber (http://en.wikipedia.org/wiki/Vulcanized_fibre). The speakers I got at Goodwill at $15 a pair, but you probably wouldn't go wrong buying/finding a better pair. The Lepai amplifier I got from Amazon for around $25, but took a while to ship from China. Dremel I got for around $35 (actually a Black and Decker rotary tool) but if you have one you obviously won't need to buy one. Drill and screwdrivers I had, and the audio cable I got from Radioshack.
Step 2: Taking Apart the Speaker
I had some cheap speakers from Goodwill. They turned out to be cheaper and cheaper the further I disassembled them, but still have okay sound. I just unscrewed the back cover, so I could have access to the speaker inside.
The speaker was held in place by four more screws, and came out fairly easily. My speakers had some sort of tiny disc that I guess was supposed to be a tweeter, but seemed pretty much ineffectual (I ripped one off, can't really tell the difference). If the speakers you get have tweeters, then try not to disconnect them when you take the speaker out of its enclosure.
Step 3: Prepping the Suitcase
The next step is to check out your suitcase. I simply measured my speakers, then traced the outline on the inside of the suitcase. Once you've figured out a good place to cut out the holes for the speakers, find a good place for the amplifier.
The holes I cut using a plastic/soft metal cutting attachment for the Dremel. I used that to kind of trace where I was going to cut, then used a simple cutting disc. Luckily, the vulcanized fiber is fairly soft, so after cutting I could use the sander attachment to make it a little neater looking.
Once you unscrew the case of the little Lepai, you might notice the outline is quite irregular. This made for some trial and error for cutting out the holes for it. You want to cut enough that you're not forcing it in, but not too much that you have empty space, and you can still screw the screws of the faceplate in. I tried to trace the outline, but it took many tries of cutting, sanding, trying to fit it in, then sanding some more, trying to fit it in, et cetera. Just try and take it slow, no need to shove it in and possibly damage the components (I may actually have messed up one of the LED lights, but I can live without that).
After you've drilled the holes, simply screw everything in. I had to drill some holes for the screws, but I used a slightly smaller drill bit size than the screw, then used force when screwing the screws in, and the material was soft enough that the screws made their own threading.
Step 4: Final Steps
All you need to do now is cut a small hole in the back to fit the power adapter cord and audio cord. I was going to make a neat little door, but a small hole was good enough.
I also wrapped the audio cord around the handle of the suitcase, which actually makes for a nice place holding my iPod. (Since my iPod is also my camera, I can't really take a picture of it there) I also had some velcro adhesive stickers so that I could velcro the AC adapter onto the suitcase itself for better portability, but that's far from necessary.
Step 5: Adding the Battery
This step requires some basic soldering, and also likely dangerous and unsafe voltages (just because I managed to not hurt myself doing this doesn't mean it's safe).
I bought a SLA (sealed lead acid) 12v battery at 7.2 amp Hours from Amazon. I think it should make the stereo go for several hours, but I haven't really done any extensive testing. If you need a primer to learn about batteries like I did, this is a good start: http://www.ashdale.co.uk/items/products/ups/batteryreplacement/batteryguide.pdf.pdf
Basically all I did to connect the battery to the stereo was buy a DC power plug from Radioshack and some alligator clips. Attach a red wire to the red alligator clip, and a black wire to the black alligator clip so you know your negative and positive. Definitely don't want to get those confused. Then attach the wires to the DC power plug (I had to use a multimeter against the AC adapter to make sure I got the positive and negative in the right places).
Step 6: Adding a Solar Panel
Since I added a battery, I needed a way to charge that battery. I liked the idea of a solar panel so I could take it to the backyard or on a picnic and not worry about plugging it in (so long as I had around 10 hours of direct sunlight).
I bought a solar panel with a charge controller that is specifically designed to charge 12v batteries, so basically perfect for my needs.
It was around $30 when I bought it, which I guess is fair enough.
To connect the solar panel to the battery, I just connected the wires to the charge controller, and then using the supplied alligator clips, just clipped it onto the battery along with the other clips. It look a little bit of doing so both pairs were secure.
Then I wanted to mount the solar panel so I could move it around depending on where the sun was, and where I wanted the stereo pointed. So I bought a couple hinges from my local hardware store, and simply screwed them into the back of the suitcase, and screwed the solar panel onto the hinges. This was made super easy by the fact that the solar panel metal housing had available holes.
Step 7: Last, But Not Least, Bluetooth!
I also decided to add Bluetooth, and frankly this is both cooler and easier than adding the battery + solar panel combo. All I did was buy a Bluetooth receiver off of Amazon (not quite the bottom of the barrel, but still cheap) and plug it into the aux/stereo mini cable. As a bonus, the color scheme matches the amp!
I haven't noticed any degradation in the sound quality at all, which I was pleasantly surprised by, and it's really cool being able to browse the Internet on my iPod and play music at the same time.
$22 on Amazon, but that includes a charger, USB cable for the charger, an RCA to Stereo mini cable, and a pair of crappy headphones.
The only downside is the receiver has its own battery, so it can go out while the rest of the stereo is running fine and you have to recharge it, but the battery life has been pretty good from what I've seen.