Compact Whistle (loud)

This is a work-in-progess, however it's a pretty loud whistle as is, so use with caution. The thickness is 5mm and the diameter is 40mm. I would like to get it down to 4mm thick, but haven't figured out how to tweak it to keep it loud. So far, every time I thin it down, I lose a lot of volume. There's a hole so it can be put on a keychain.Printed with a Bambu P1P0.4 nozzle0.2 layer height2 walls (If not printing correctly for you, try bumping it up to 3 walls)No supports needed. Prints really fast - about 5-6 minutes.If you print it, please leave a comment, show a picture, and let me know how it worked for you.