The article ends to a link to a video that shows off the technique and it blows my mind the Spectrum beeper could produce this: https://www.youtube.com/watch?v=7cOu32m3wvQ
I created a program like that back in the day. In my case, I recorded my voice through the "MIC" input and played it back through the TV. A few seconds of sampled audio required the entire available memory. While I fully understood what was going on, I thought it was magical that the Spectrum could "speak with my voice".
More mind blowing, that entry took _second_ place! First place would probably break my brain for the day so I won't look it up.
Release party: DiHalt 2026 summer Compo: Demo Platform: zx spectrum Ranked: 2nd
Sounds pretty good. Reminds me of the Demo Scene and the types of music they were able to create.
I gotta try this on real hardware, reading the original article it seems it's barely audible without an amplifier, unlike on an emulator.
Will post an update after I get back to my parent's home, where I have these beauties that launched me into computer science: https://imgur.com/a/GKrA0vX
Turns out that it's actually 2-bit and not 1-bit. It uses a combination of the EAR and MIC jacks, and when you output through the MIC jack, it slightly boosts the EAR jack. That gives you 4 possible levels, but they are not evenly balanced.