music from a fixed location in your home to mobile. >> you are witnessing the ultimate miniaturization of the cassette player. never has so much genius been coaxed into so little space. >> in all the great bursts of innovation, there is always some kind of scientific break through that has to happen first. and none of this stuff could have happened in the 1980s without the transistor being invented in the 1940s. and japan in particular understood that they could make things smaller, more versatile. sony was brand name that really mattered in the 1980s in technology. >> i'll take the sony! efrmgts the original sony walkman was so solid it was a pleasure to hold. it had density, heft. >> pop it in, close it. a very satisfying sound. not just click click.