San Francisco's aren't as bad as I thought.

[coppercarl]

I was doing a search of the sirens in San Francisco's sirens. I found a site that had some sound on it and it turns out the sirens run in attack. Not the 15 second test tone repeatedly.

Here is a post I put up that will explain what I am talking about.

http://www.airraidsirens.com/forums/vie ... php?t=6791

And is is a site with the attack. (Note this is what they use for all warnings)

http://72hours.org/sirens.html

Click the button that says "listen" with the speaker.

[ermaff6231]

its the same crappy thing its an ati with an stl-10 tone

[dilloncarpenter]

Thats a LITTLE better....but Federal Signal may have a suit on their hands! that sounds exactly like an STL-10.

[MattDean1003]

That's because it's an STL-10 tone being reproduced over the sirens.

[Adam Pollak]

If the sound were that of a Federal Q, which they have a registered Trademark for, they could sue for infringement, unless they granted permission. ATI made a recording of a San Francisco STL-10 that they used for that recording, so that is the sound you are hearing. Similarly, Wichita Falls, TX has a T-Bolt recording that plays over their Whelens.

[Tannre]

What can you expect from ATI? I mean come on, the signal in their control boxes reads TBOLT CNSR.

With the STL-10 tone, it honestly wouldn't surprise me if the control boxes had a tone called STL10 SUB.

[Adam Pollak]

This is a recording a friend of mine made in June for me in San Francisco of the weekly test.
http://www.youtube.com/watch?v=Npgh5zQtpBE

[MattDean1003]

IMHO, that's pretty loud and clear, and it's doing exactly what it's supposed to do. Except for that little whine right before the siren goes off, it sounds crisp and clear. Granted, it does sound better than the standard tones they use. I've yet to hear the ATI's up here in GA yet.

[ginbot86]

The STL-10 tone definitely sounds better than a 1 kHz tone, but the low tone of the STL-10 recording (hence, STL) can damage siren compression drivers, blowing them out; they are rated for frequencies above ~200 Hz.

[Daniel]

Perhaps ATI should consider using drivers like those found in European electronic systems by H?rmann, Wandel & Goltermann, and so forth. Many of those countries mandate the peak frequency for a siren's output at 440 Hz., which is only slightly above an STL-10.