This stuff makes my head hurt.
Sine-Wave speech or synthesis was first developed in the 1970s by Philip Rubin at Haskins Laboratories. It’s a way of replacing speech formants with pure sine tones, which are still entirely comprehensible once you know what to listen for.
The Universe Of Cambridge has a quick Introduction.
If you’re not listening for speech, these sine waves might just sound like garbled nonsense. But once your brain knows, it knows. Scientists call this “perceptual insight.” Once you’ve heard the examples and know what to listen for, it’s easier to interpret things. Even if you can’t consciously recall every word of a spoken sentence, when you hear it again as a sine-wave, it’s still pretty clear.
This project by Václav Volhejn is an interactive example, and lets you bounce back and forth between his original voice and sine-wave speech. Check it out.
Things get weird, though, when you’re primed to hear two different things. This was shared after the first trailer for Steven Spielberg’s Disclosure Day came out, since the aliens in that movie appear to use sine-wave speech to communicate. In the third video, you can hear it say two entirely different things depending on what you prime yourself for.
What’s that say about human perception?
