At one time the words portable and audio probably sounded akward in a sentence together. Today, that's much different– nearly everyone I know has some kind of portable audio device, or at-least is lusting after one. CBC Arts Online has a great photo essay about the evolution of portable audio written by Matthew McKinnon called Bring the Noise. He takes us through the history starting out with the old pocket transistor radio in 1954 made by Regency to the reminiscent times of the super woofer boom boxes in the late 1970's and early '80s all the way to the present, the age where the iPod and wearable audio reign supreme.
via Core 77