That's very interesting. Does it produce a recognizable hen sound, or is it just a sound wave that falls within a certain frequency?
Each area sounds like a turkey.
I also had an ocarina made to the same range of frequencies. An ocarina is basically a flute. It sounds nothing like a turkey but they come to the sound of it. They all come! Toms
Jake's and hens!
During the off season I made electronic sounds. They sound like all kinds of things such as crickets and some really weird sounds in the same frequencies and the turkeys show up! It's kind of funny! They are birds of sight and sound and are very curious. They come out of curiosity.
Some time in the coming week I am going to machine a chime holder and will make chimes in the same frequencies to try out. I'm sure they will also work. I will cast the chime holder with the same ceramic. The ceramic side can be struck with the striker the chime side will get hit with the striker.
It has always made me crazy to only be able to call toms. Tome that are with hens won't usually come. I want to call hens! If the hen comes the toms will follow.