Norio Ohga, the Sony executive who shaped Sony into a media empire and oversaw the development of the compact disc, has died of in Tokyo of multiple organ failure. He was 81.

Ohga was a former opera singer who first gained the notice of Sony executives when he wrote a strongly worded letter to the company, complaining about their tape recorder’s many failings. That led to a job as a part-time consultant, and over the years Ohga rose in the ranks to become chairman and chief executive, influencing the direction Sony would take in everything from the sleek, black design of the Walkman to the company’s acquisitions of CBS Records and Columbia Pictures, which led to Sony becoming the vast global entertainment conglomerate that it is today. And in the ‘70s, it was Ohga who shepherded the CD into being, insisting as a music lover on a format that could play continuously for 75 minutes—long enough to contain all of Beethoven’s Ninth Symphony. Along with changing (for a couple of decades, anyway) how people listened to music, Ohga was also a driving force behind the Sony PlayStation. Needless to say, the last 30-plus years of technology and entertainment would have been slightly different without him.