Sony Portable Audio in 1990

By 1990, the balance Sony had maintained between cassette and compact disc was beginning to shift. The company was still developing both formats aggressively, but the direction was becoming clearer. CD was no longer being adapted to fit into portable form. It was starting to define what portable audio would become next.

This change did not happen through a single product, but through accumulation. Discman models continued to improve in size, stability, and power efficiency, making them more usable in everyday situations. At the same time, Walkman remained highly refined, benefiting from years of mechanical and ergonomic optimization. The difference was no longer about quality. It was about trajectory.

What makes 1990 distinct is that Sony was no longer treating its formats equally in terms of long-term vision. Cassette was still essential, still dominant in many markets, but CD had gained momentum that could not be reversed. The company was no longer trying to perfect everything at once. It was beginning to move forward, even if it had not fully let go of what came before.