How well does it work? See the videos below. Short notes, as well as note-offs, tax the quad motor’s ability to stop the siren rotor immediately. There’s a nice portamento effect as it ramps ...

The basic idea behind [Matthias]’ air raid siren is to make two impellers that force air through two stators along the perimeter of the rotor. As the siren spins, the air coming from the ...

The loud noise that awoke residents across parts of Northwest Columbus and surrounding suburbs on Saturday morning was caused by a malfunctioning tornado siren at Centennial High School.