The trouble is that sounds and techniques of achieving them change greatly.
The Italian Vox Umani is two flute pipes beating against each other. https://www.youtube.com/watch?v=tw8KCZR40Co
The reed version also needs a flute to beat against. If this is done properly as at St Maximin, the sound is sublime. The pipe is very similar to the Cromorne, the transition from Krumhorn to Clarinet, and again at St Maximin built by Isnard in 1775 the sound is sublime.
If anyone has the Hauptwerk St Maximin sampleset perhaps someone might be able to demonstrate. Whilst playing the real instrument the rank of Cromorne is right behind the bench and unsuspectingly one jumps out of one's seat whilst playing.