What on Earth is going on here?

[Model2]

http://www.youtube.com/watch?v=S5zEozyM ... re=related

[E712]

That certainly will get your attention, I wonder whats causing it to do that?

[ver tum]

That has to be a custom tone. My guess is that it's a Modulator or DSA, but it could also be a Whelen. The Netherlands has a similar custom tone on their Mods, and here's a recent video of what they sound like from a distance.
http://www.youtube.com/watch?v=psMRMidj7yo&fmt=18

[Notre.Dame1003]

The low tone at the beginning can't be good for the drivers.

[holler]

I think New Ulm has an ASC E-Class.

[ver tum]

The low tone at the beginning can't be good for the drivers.

If it's a Mod it shouldn't hurt them. The Mod at the University of Louisville used to start up and wind down to about that pitch when it had the older controler in it, and I never heard it clip.

[Crazywarriorman]

There was a thread about this awhile back somebody said it was a mockingbird whistle.

http://www.airraidsirens.com/forums/vie ... 8ab44eac6c

[siren_face2000]

I for one like that tone for some reason. It's definitely not bad on my nerves!

[t-bolt82]

The first vid, with the storm warning -- that is creepy as hell! The 2nd one is as well, but it sounds sort of like a crazy synthesizer or something!

[german_siren]

it weould be interresting when one finds out what it is actually!