|How hydraulophone work, images from university of Toronto.|
I search on google about how to make a Hydrauophone and i find this link wearcam.org/acmmm2006presement_as_published.pdf If you clik that link you will showed journal pdf document titled Hydraulophone Design Considerations. There are showed that it make by Steve Mann, Ryan Janzen and Mark Post.
From that journal, if i true, Hydarulophone is modified from piano. And i think to play Hydraulophone like piano too. This is genius idea, make musical instrument from water. Its very awesome, i hope you can get inspired and you can make your own musical instrument, maybe someday you can make musical instrument from fire, snow or anything.