Loudest Air Horn (Prank) Air Horn will help you make prank your friends with various sound effects, such as an air horn, siren, car signal and other frightening sounds. Choose the right sound effect for you and have fun.It includes various realistic sounds such as air horn, train, ship... which will fool everyone. Every event is better when you pump the air horn as you stroll in. Killed it at a meeting? Air horn. Nephew just got baptized? Pump the air horn alongside the choir.