Read the full feature at Wired:

When music became handheld, music changed. Even with the advent of modern stereo systems in the first half of the 20th century, listening to music was still a shared experience. When you walked down the street holding the Regency TR-1 next to your ear in the mid-1950s, just as rock ‘n’ roll was becoming a major cultural force, music took a huge step away from performance toward becoming private.

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