Bike Stereo

Build a sound system for your bicycle and entertain your friends. The speakers are designed to fit within the frame and can be easily removed. My system is powered by a battery operated mobile T-amp and an ipod. The total cost of the system is well under $100 and can be completed in a few hours.

Here are some of the things you will need to get started.
1. A good pair of tin snips.
2. Velcro Tape.
3. Pliers
4. Wrench
5. Sharpie
6. Spray Paint (optional)

NOT PICTURED but still important:
7. Speaker wire
8. 1/8" line to go from the source to the amp. (mono is probably better than stereo since the speakers face opposite directions)
9. A sturdy basket. I got mine at IKEA in the bathroom section for 4 bucks.
10. A drill and a bit that will go through aluminum duct.
11. An old leather belt.

Check your local hardware store for sheets of HVAC aluminum ducting. My local store was out so I went to Home Despot. They had several shapes and sizes. The big sheet was 7 bucks but I managed to cut two pieces out of a smalled pre-bent sheet for under 4 bucks. If you measure your bike frame first and bring the stencil you cut out you can make sure you get the right size.

Sonic Impact Portable T-Amp Digital Audio Amplifier. This is a battery powered 15 watts per channel stereo amplifier. It costs about $30 new. It runs on 8 AA batteries. I'm using POWEREX 2300 mAh NiMH rechargeables from Thomas-Distributing. They cost a bit more but you only have to buy them once and they last forever. I've run the amp at full blast for 3-4 hours without running dry.

Sonic Impact Stick-On Speaker SoundPad Pair. These run about $20. These speakers stick to any flat surface turning it into a speaker. In this project I make two flat planes out of aluminum that fit inside my bike frame. The sound pads are concealed between them and the sound actually comes out of the aluminum!

You will need a source for your sounds. I use and iPod wraped in an iSkin for protection. You can't be too careful these days. The best part about the iSkin is the clip on the back which I use to secure it to my $4 IKEA basket. You could easily substitute another mp3 player, a walkman, or discman. If you figure out how to put a turntable or an 8-track player on a bike, let me know.

You will need a bike. This is my '68 Schwinn Racer, made right here in Chicago.

Using a large section of cardboard, posterboard, or paper outline the inside of your bike frame. This will help you cut your aluminum speakers to the proper size.

Cut out your stencil. Now you have the shape of your frame so you can chop your aluminum down to size.

Use your stencil to cut two speaker planes out of your aluminum sheet. Don't worry about the excess aluminum. It will be bent in the next step.

Make sure you make each plane slightly smaller than the area of your frame so it doesn't rattle and scratch your paint.

Cut two even parts from the belt. About 10 inches each should do. Drill 2 holes through the aluminum planes, one towards the front and one towards the rear. Use bolts with locking nuts to hold the belts in place. Hang the planes over your crossbar like saddlebags.

Stick the speakers on the inside of the panels. Place one higher and one lower so they will not hit each other when they are hanging back to back. I also added a strip of velcro tape around the bottom bar on my bike frame to stabilize the speakers so they would not swing side to side and hit the pedals.

I spliced some female RCA jacks onto my speaker wire so I could easily remove my amp from my bike.

My Sonic T-amp came with long male RCA speaker cables. I trimed them to about 6 inches so they wouldn't get caught in the front wheel.

On my first test run, I just set the T-Amp in the basket. I hit a pothole and almost lost it. Luckily, I caught it due to my incredible Nintendo reflexes. Since then I used twist ties to fasten the battery cover to the basket. The T-Amp just clips onto the battery cover and I feed the speaker cable through the bottom of the basket.

I stick one side of the velcro tape around the handle bars. The other side wraps around the basket and attaches to the bars holding the basket in place. Rope or a strap also works pretty well. The velcro tape can be easily removed and replaced when you want to take your basket with you. I've found that the velcro sometimes needs adjusting on a long bike ride.

Plug the 1/8" line into the iPod and the line in on the amp. Plug the speakers into the amp. Slowly crank up the ipod and the amp. If either source is too loud you might get a tinny rattle. The bass isn't great but it sure beats whistling. If one or both of your speakers isn't working, try reversing the red and black wires on the speaker cables. You may have spliced them backwards.

I painted mine to match my frame. I'm working on a stencil and logo to spice it up a bit more. Any suggestions?