Tube Whistle

**WARNING: This whistle can produce sound at the level of a leaf blower, rock concert or chainsaw. Hearing protection is recommended.**

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This whistle makes noise based on the same concept of making sounds by blowing over a bottle opening.

It has 4 different depth "tubes", each creating a different frequency sound. They combine to make a very loud noise in a small package.

The design includes a hole for a keyring so you can always have it handy in case of emergency.

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Update 1: Due to some printing artifacts, I found it difficult to blow through the whistle (the output slot was too constricted), so I enlarged it (Whistle_V2_10.stl). I got higher decibel sound pressure, but actually find it not restrictive enough (cannot blow very long), so I'll be making a 3rd version with the slot in between the first two versions.

I also added some bumps on the mouthpiece, so that it can be held in your mouth with your teeth — so you don't spit it across the