Here is part 2, unlike my first video it didn't quite hit it in the sound department for the Allertor & Banshee 110 siren sounds. 1:25 when taken to 60HZ sound at 6,900/ 7000 rpm
The start of the video this siren was taken to 5,800 rpm to show how a 10/12 version would sound at 2,900 rpm on 50HZ.
In this video I even ran this siren at a pitch first up of how one of those 10/12 sirens would sound on 50HZ before taking to to peak pitch like one does at 60HZ.
The use of 4 middle blades placed inside of the rotor then the intake/base gets this sound.
There is an improvement in the sound to last time.