The upright bass (or double bass, contrabass, string bass, or bass violin) is a rather conservative, stayed instrument. Of the violin family tree, it appears to be the most root-bound member. Enter the Upright Double Bike. 100 watts of amplification, pushed through 4 musical instrument speakers and a pair of tweeters, powered by 36 volts of onboard batteries, and all rolling on wheels, this postmodern revision finally gives bicycle artists everywhere the wherewithal to really get on down.