For those too impatient to read the details, check out the "Hear for yourself" examples toward the bottom of the page. They're reproducing decent sounding speech at 1.6 kbps.

1.6 kbps is nuts! I like to re-encode audio books or podcasts in Opus at 32 kbps and I consider that stingy. The fact that speech is even comprehensible at 1.6 kbps is impressive. As the article explains, their technique is analogous to speech-to-text, then text-to-speech.

The original recordings are a little stiff, and the encoded speech is a little more stiff. It isn't perfect, but it's decent. It'll be interesting to hear this technique applied to normal conversation. If regular speech holds up as well as their samples, it should be perfectly adequate for conversational speech. At 1.6 kbps, which is absurd.

Also, I wonder how well this technique could be applied to music. My guess is that it won't do justice to great musicians ... but it might be good enough simple pop tunes.