Listening to music adds an extra dimension to the fun of riding a bicycle. When I originally built there, there were no widely available portable music systems that sounded reasonably good, could be heard when standing next to a bus, were vibration and weather resistant, and had enough battery life for a 4-6 hour bike ride. So, I built this prototype.
The shell is made from sonotube that’s been painted with boat paint. There are two marine speakers on each end. Sandwiched in the middle is a 12 volt SLA battery and a stereo amplifier. I 3D printed a control panel and mounted the volume knob, audio input jack, and a charging port to it.
I used this system on daily rides for several years before it finally fell apart (it’s since been replaced with an upgraded portable system, still to be documented).