You'd end up with more or less a reed instrument. It's actually possible to get some notes out of a brass instrument using a woodwind reed, albeit that it's not

You'd end up with more or less a reed instrument. It's actually possible to get some notes out of a brass instrument using a woodwind reed, albeit that it's not easy and doesn't seem to be able to produce more than a very limited range: https://www.youtube.com/watch?v=NFDNY9_W0ws https://www.youtube.com/watch?v=NFDNY9_W0ws A simpler example would be the type of vuvuzela which has a double reed embedded in the tube, so that just blowing into it causes a loud honk.