Put your fingers in your ears and scream? :D
I wonder too about the effects of the decibel levels of crowing on the birds....geeeeezzz it's LOUD! The girls can be pretty damn loud too.
I hope you get this thing and see if it works, it's a fascinating concept.
Not sure the noise would distract them enough to making them stop vocalizing(like it does with dogs)....or make them crow more.