I'm sure we can do better today even without ML, I'm sure our hypothetical Lua-Machine can do better... Which I understand @patchlore is working on...
But I'll describe the iconic model of a vocal tract a rushed Dennis Klatt implemented in the 1980s for a then-recently paralysed Prof. Stephen Hawking. Since that's what I'm familiar with!
The primary component of which is a "resonant" which is a multiply-sum over its 3 most-recent inputs. We stack a whole bunch of these!
2/3!