Wind and brass instruments (which I’ve just learned are collectively ‘aerophones’) work because since characteristic of their shape causes the air that is pushed or drawn through them to vibrate at particular frequencies. They work in air whether you’re down a mine or at the top of a mountain, so there’s clearly some tolerance to pressure variation. I presume, therefore, that you could play them using other gases too (e.g. by connecting a whistle to a pump in a nitrogen atmosphere, for example), albeit presumably with a change in pitch (we have whistles driven by an air/steam mixture on steam locomotives, for example).
But I wonder: can such an instrument be used with other fluids? How about a liquid, like water? Can I pump water through an underwater whistle in order to make a whistle-like noise? What are the physical constraints on doing so (e.g do I need a higher pressure difference in water)?
If it’s not possible, why not? What could be done, hypothetically, to construct an aerophone-style (“hydrophone”?) instrument that would work underwater?
tl;dr: Could I pump water through an underwater whistle to ‘blow’ it? If not, how can I ‘fix’ that?