This is part of beta version of Cyber Music Studio™. It's not finished yet and can be broken at any moment.
Feel free to test it and report bugs here.
In 1980s CASIO released series of inexpensive Casiotone keyboards. Some of them were using mysteriously named vowel-consonant synthesis.
It's description in US patent 4419919A sounds complicated but it's very simple in fact - it uses two square waves with different envelope filtered by static low pass filters.