Sometimes inspiration takes me in strange directions. Yesterday, I had an impulse to see if I could make a functioning whistle. Don’t ask me why!
I did some research to see how they worked and I watched a couple of videos. Then I started playing. Trial and error finally led me to the right dimensions and I made a Pea Whistle. (Please excuse the crappy paint job. I was just so thrilled that it worked and couldn’t wait to share.)
When I first put it together, it didn’t whistle. No matter what I did, I got no sound from it at all. Frustrated, I continued researching and was unable to find what I might have done wrong, much less a solution. I was about to throw it away when I gave it one last try and I actually squealed with glee when I heard a clear whistle blast. I guess it just needed some seasoning!
Anyway, from weird inspiration to the final working prototype, this is my Pea Whistle!
I’ve been looking at whistles online. One thing I noticed is a lot of them have a ‘scoop’ to help make the sound; all of them have a larger air hole. I think if you enlarge it (take space from just in front of the yellow flower) and give the opposite edge a slight taper, it will be easier to make the sound.
@kelley1 Thank you. The anatomy of a pea whistle is pretty standard. I did taper the space that you blow through and the air chamber is large enough. I am making some more today, so we’ll see if they behave the same way.
A broad group of blowing noisemakers work by what is called a vortex street. As a smooth flow hits an edge the splitting air column twists up and then down very rapidly making the sound till the resonance follows the size of the air column. Everything from whistles to flutes work this way. The key is to have a smooth flow just touch that sharp edge.
Better explanation from Quora …
How does a whistle make sounds?
Whether it is a silver flute, bamboo sakuhchi, wooden recorder or penny whistle, all of them share a similar feature. It is called a “wind cutting” edge. When air is forced across this edge at the correct pressure (i.e., wind speed), the flute’s internal air pressure will tend to cycle between over-pressure and under-pressure. This oscillation, depending upon the pipe’s diameter and length, will vary but the flute’s general range is between 250 and 8,500 oscillations per second, called Hertz or just Hz.
Way to think of trying a whistle! I am always thinking of what I can make with my GF and I would have never come up with this. Now that I know it can be done I might have to try. I just can’t let my 3 year old get ahold of it or I might lose my hearing!