Fascinating NYT article this morning, https://nyti.ms/2yVqUS8
Researchers put beat-boxers into an MRI, and recorded the motions while they were making full drum-kit sounds vocally. Amazing mouth movements, some of which are like speech... and others, which don't seem to appear in any human language!
Lessons for anyone interested in how the human instrument actually works. Which, after all, is what we spend most of our time documenting.
...the researchers apparently were looking for the same kind of information, to help develop language-independent speech recognition and synthesis.