Hello everyone,
Back in the early 1980s, I had the unique opportunity to work at Capitol Records in the Toronto, Ontario area. While the company produced both tapes and records, my role was centred in the tape manufacturing plant.
At that time, quality control was a completely manual process—each product was reviewed by ear, making the results highly subjective. To improve consistency and reliability, three of us collaborated to design and implement a new quality control system. This system consisted of two custom cards: one plugged into an Apple ][+ computer running custom firmware, and the other was an analog board equipped with band-pass filters targeting the specific audio frequencies we wanted to monitor. The analog board interfaced directly with the digital board inside the Apple computer.
Remarkably, our system remained in use for over a decade, right up until pre-recorded tapes were eventually phased out.
Now that I’m retired, I’ve put together a video sharing more about these experiences. If you’re interested, you can watch it on YouTube here:
Thanks for reading!
That's pretty neat.
Tell us more about the supporting hardware.
You correctly indicated that the Apple II is incapable of analyzing the audio spectrum in real time and displaying it on the screen, so the supporting hardware must have done most of the heavy lifting.
Also, from the bootup sequence, this appears to be a DOS 3.3 based system, and at least the introductory screen seems to be written in AppleSoft, or am I wrong?
I'm curious about this