Lou Ottens, the Dutch engineer who created the technology behind cassette tapes and compact discs, has died at 94. He passed away at his home in Belgium on Saturday, reports DutchNews.nl.

After studying to be an engineer in school, Ottens got his start in the industry when he joined Philips in 1952 and, eight years later, rose through the ranks to become the head of the firm’s product development department. It was there that Ottens led his team in developing the first portable tape recorder. Two years later, he revolutionized the reel-to-reel tape system by inventing a miniature version known as a cassette tape.

When the first plastic cassette tape made its debut at a 1963 electronics fair, it boasted the slogan, “Smaller than a pack of cigarettes!” Ottens specifically designed the cassette to be tiny enough to fit in a jacket pocket, in part because he found other  tape models to be unnecessarily large. “I got annoyed with the clunky, user-unfriendly reel-to-reel system,” he said years later. “It’s that simple.”

Instead of keeping his invention private, Ottens urged Philips to license his design so it could become an industry standard and reach a wider audience. Philips listened and made a deal with Sony to use the patented mechanism. Without missing a beat, Japanese companies quickly copied the tapes over to different formats while Sony rolled out a standard cassette globally. All told, over 100 billion were sold worldwide.

As noted by music journalist Marc Masters, who is writing a book about the history of cassette tapes, the original prototype that Ottens’ team invented was created as “an opportunity for journalists or nature lovers to make sound recordings outside,” not as a way to listen to popular songs. “The very first one, we said, well, speech is good enough,” said Ottens. “Then we came to the conclusions that [the sound quality] was much better than we had anticipated. We said, if it’s made for music, we should have 30 minutes per side.” And thus, the cassette tape as a portable album was born.

Several years later, Ottens changed the game again when he helped develop the compact disc, a new Sony-Philips standard that revolutionized the music industry. Of course, CDs became a lasting global phenomenon, selling over 200 billion copies and becoming a staple for physical media.


Despite the recent boost in cassette sales in the modern day, Ottens held the firm belief that CDs were better than cassette tapes until the very end, arguing that “nothing could beat the sound of a CD.”

As for his own legacy, Ottens remarked, “I have no ‘pride dial,'” and instead credited the team effort that went into creating the products instead of himself.