I got a short video of the 6 PM internal test they do on the new sirens in my city. The siren head rotates and when it stops the siren sounds off . There is some background/wind that my camera mic caught and you hear a break up in the sound , its not the siren . I will get the full monthly test on video next month.
http://www.youtube.com/watch?v=0NG4fdru9dc
Those sirens sound really great.