RIP Lou Ottens, Developer Of The Compact Cassette And More

It’s with sadness that we note the passing at the age of 94 of the long-time Phillips engineer Lou Ottens, who is best known as the originator of the Compact Cassette audio tape format that was so ubiquitous through the later decades of the 20th century. Whether you remember cassettes as the format for 8-bit software, for teenage mixtapes on a Walkman, they began life at his hands in the early 1960s at the Phillips factory in Hasselt, Belgium.

Through a long career with the Dutch electronics company, he was responsible either directly or in part for a string of consumer electronic devices that we would see as ubiquitous over the latter half of the century. Before the cassette he had developed the company’s first portable reel-to-reel tape recorder, and in the 1970s while technical director of their audio division he led the team that would develop the CD. He was reported as saying that his great regret was not beating Sony to the development of the miniature cassette player that would be sold as the Walkman, but we’d suggest that the Walkman would not have been possible without the cassette in the first place.

So next time you handle a cassette tape, spare a thought for Lou, an audio engineer whose work permeated so much of the last half-century.

Thanks [Carl] for the tip.

Images: Lou Ottens by Jordi Huisman CC BY-SA 4.0 and “An early Phillips cassette recorder” by mib18 CC BY-SA 3.0


30 thoughts on “RIP Lou Ottens, Developer Of The Compact Cassette And More

      1. A clear Leader, always ready to be taken up. At age 47 he flipped over for a second run at life.
        Dolby surprised if his legacy isn’t indelible, hiss-tory has punched out his protection tabs.

        1. *groan* 👏 I thought “wow” when I heard the news, I could hear my heart flutter, have to admit I have a bias toward his remarkable work–RIP Lou. According to Wikipedia the cassette was also called the musicassette–never heard it referred to that way! I wonder if Lou had anything to do with the short-lived Phillips digital cassette.

          1. I found out that he got spliced in 1955. But after a strange twist his life went into reverse for a while, or it sounded like it anyway. At least his legacy won’t be erased from history!

  1. He was also the father of one of my schoolchums but i only met him once. He had a framed golden casette (knowing Philips it was probably just gold plated) on the wall in his home office.

  2. I hear he’s going to be laid to rest in a giant jewel box. Still he made a great contribution to the 20th century, can you imagine loading programs off reel to reel!?

      1. I did some cassette splicing. Nothing artistic, just cheaper to buy regular length cassettes than 10 minute ones. So cut them and splice them to get very short cassettes. It was easier for programs I loaded a lot to keep them as one program to a tape, rather than having to fast forward for a specific program.

        I think “tape splicing” may still be used, even though it’s all electronic now.

      2. I heard on NPR once that before Washington went digital they had 120 workstations of a reel to reel, headphones, razor blade, marking pen, and 3M splicing tape. At 15 inches per second it’s easy to rock back and forth and pen mark where to cut. Now it’s a drag and delete. I got to where I’d poke a two needle pronged dowel into each cassette hub and be able to back cue the source cassette when making a mix tape.

  3. When I learned about magnetism and B-H curves in school, I couldn’t for the life of me understand how you could make a cassette tape work at all, since there was a huge hysteresis effect for any practical magnetic material and you just couldn’t get it to respond directly to an applied magnetic field. The signal that you could record would be extremely non-linear and depend on what was already on the tape.

    Then I saw a circuit diagram for how a cassette tape recorder actually worked. It was brilliant. If I remember it correctly, there’s a 150 kHz or so carrier wave that keeps on flipping the magnetic field over from one extreme to the other, and the duty cycle of the carrier is modulated by the audio signal to be recorded, so when the tape moves past the head it leaves behind the average field strength despite the hysteresis of the tape.

    As the tape moves under and away from the head, the magnetic field on the tape is pulled strongly towards one extreme, then the other, then slightly less to the opposite, and slightly less to the other opposite, diminishing as it goes further away from the write head, so it converges somewhere in the middle. Since the back-and-forth flip is done at a much higher frequency than the signal you’re recording, it converges to something very close to what you want to record.

      1. There were cheap transistorized reel to reel portables in the early sixties. As I recall, no capstan so the speed wasn’t constant. And a permanent magnet to erase. But I’m not sure if they had bias oscillators, too young to know at the time

  4. It’s easy to forget how the cassette opened up new opportunities to capture audio out in the world. My dad bought one of the early Norelco recorders around 1965, and pointed the microphone at whatever caught his fancy. His recording of the 20th Century Limited passing at 100 mph was just one brief, amazing whoosh.

  5. I was finally able to convert my recently arrived conversational Klingon audio tape to MP3 after the sixth cassette player I tried showed sufficient signs of life to work.

    Keeping cassette players working will be an ongoing challenge, but the data should be pretty safe, perhaps safer from the ravages of time than CD/Bluray storage.

  6. I regret not getting rich off that walkman thing. I had a Norelco carrycorder and later made it into a stereo car and portable with the head and guts out of a Craig car unit whose mechanics were crap. It sat on top of a box that contained a 12 volt power supply. What I wanted was one of those pocket sized dictation cassettes that ran smooth (some didn’t) and had play only but in stereo for headphones. In 1971, it was possible just ahead of the time. Senhiser 414 headphones and the original carrycorder in mono sounded as good as a home rig but was portable, but I wanted stereo and pocket size.

  7. I remember in the late 70s working on my Master’s in EE and using cassette tapes with Bill Gates invented Operating System called CP/M. The tape would sometimes get stuck and that required slice and dice repair but it was always fun!

    1. For a guy with a Master’s in EE you have a very poor grasp of this part of computer history. Gates didn’t “invent” CP/M. He didn’t even “invent” DOS – he ripped off a company called Seattle Computer Products to get that. CP/M came from Gary Kildall’s company Digital Research, who dominated the microcomputer OS market back then. Totally different people and thing. And why IBM went with DOS – and made u$ the monster it is – rather than CP/M is another story altogether.

    2. I’m not sure if you’re trolling or not, but Gates, et. al. did not ‘invent’ CP/M.

      CP/M was written by Gary Kildall of Digital Research, Inc. and was subsequently copied by Tim Paterson who sold it to Microsoft as ‘his own work’.

      1. That’s a bit misleading. Paterson didn’t copy any code from DRI. He copied CP/M’s functionality using a CP/M manual as a reference, but he wrote all of the code from scratch. To put this in perspective, this is like writing an Apple II emulator that runs on Intel ’86 processors using Apple’s manuals as a reference. I actually did this many years ago. If anyone implied that the emulator was not my own work I would have been extremely offended, and I certainly would have defended my work in civil court. I didn’t design the machine I was modeling in software, but I certainly wrote all of the code myself.

  8. And of course cassette tape wasn’t just used for recording music, I have some analog synthesizers, an Oberheim OB8 for example, that backs up all of its settings to cassette tape–Lou really was involved with the whole notion of encoding information on portable magnetic surfaces.

  9. Philips ( watch the spelling ) had the fortune and patient to develop great engineering talent
    in the early 20th century. It is enlightening to get an insight into their apprenticeship system.

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