Bike Bluetooth Speaker
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For quite some time I've wanted to build a portable speaker I could carry in my bike's water bottle cage. I've also wanted to build a bluetooth speaker--that is, I wanted to see if I could hack a cheap, crappy-sounding bluetooth speaker & turn it into a decent-sounding portable speaker. It has taken some months to scrounge up all the necessary parts, but now I've combined both projects into one successful build.
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First, I picked up this hard plastic tube, about the right size to fit snugly into a water bottle rack. Don't laugh…the tube originally came with a toilet brush in it! Then, I came up with this 4" speaker driver, rescued from an old bookshelf-type speaker…it fits into the tube just about perfectly.
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Next…I found this little Wireless Bluetooth Speaker. These usually sell for around $20, but a local retailer currently has 'em on sale for $9.99.
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The speaker driver that's inside isn't worth a hoot, but the enclosed electronics are sufficient to power a bigger, better speaker at reasonably loud volume levels. This speaker came apart fairly easily, and all of the electronics are conveniently housed in the base of the device. I did have to lengthen the speaker wiring a bit.
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The rest is pretty straightforward…drilled a small hole in the bottom of the tube to run the wiring through, affixed the electronics to the bottom of the tube with some wood screws...
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...and secured the speaker driver with hot glue.
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As a finishing touch I added a grippy rubber thingy from a travel coffee mug to the bottom of the construction, to help keep the slippery plastic tube from sliding out of the water bottle cage.
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Although I could certainly use this as a stand-alone speaker via bluetooth connection, my plan is to use it in combination with an earlier project, my backpack subwoofer (details on this build mentioned HERE). This sub is a 4.5 inch driver in an 8" x 8" x 4" bass reflex enclosure, also powered by an internal rechargeable battery. Anyway, I'm using my iPod classic to play music while biking, & it's not a bluetooth-enabled device. It's a relatively simple matter to wire all of the devices together on the bike. Whenever I need to park & lock up, I can remove all of the vital technology from the bike & carry it with me…no worries about potential theft or vandalism.
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This bike/music idea started when I got a Jawbone Jambox & wanted to find a way to mount the speaker on my bike. Now that I have the other speakers up and running I probably won't bother to use the Jambox while cycling any more...but for the curious, I've documented my Jambox bike mount project HERE: http://jrsprintsofdarkness.blogspot.com/2013/07/the-jambox-project.html
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Update, 3/14/14 - I added a protective cover with metal grill to the bike speaker.
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More modifications (3/24/14): The electronics from the original bluetooth speaker I hacked gave me some grief (mini USB charging port broke off, etc.)...so I decided to swap everything out, rebuilding the electronics with the guts of another (non-bluetooth) portable speaker. I also added a bass reflex port tube, made out of a plastic pipe elbow from a hardware store.