Modulator and annoying siren

[MattDean1003]

Annoying off key siren
http://www.youtube.com/watch?v=fag13Jpr ... re=related

DSA sounding what is similar to the Whelen wail tone in my siren clip
http://www.youtube.com/watch?v=49AuitGwQgE

[ver tum]

Annoying off key siren
http://www.youtube.com/watch?v=fag13Jpr ... re=related

I've heard a siren that sounded like that before, in a video of Swiss airraid sirens. It sounds like the music from an old science fiction movie.

I believe that the first siren that started before that weird siren did was a Horman E-57. The E-57 sounds a whole lot like a Federal STL-10.

[CTsirenhunter]

Annoying off key siren
http://www.youtube.com/watch?v=fag13Jpr ... re=related

I've said it before and I'll say it again: I love the Swiss siren system. I have yet to see another country mix together the E-57, electronic sirens, and those terrifying and discordant but very cool Kockum KTG-9 horns. Then again, I think any simultaneous combination of sirens and horns is cool, and often more ominous than sirens alone.

[ver tum]

How do those Kockum KTG-9 horns produce that terrifying sound?

[kanazo]

sounds like an organ, are these electrical?

[CTsirenhunter]

I know that from pictures, they appear to be several air horns sticking out of a central disk-shaped thing on a pole in all directions. I guessed that each different horn made a different tone and that they worked something like a Diaphone, but I barely understand Diaphones, so don't hold me to this...

[SirenMadness]

Diaphones work like sirens in a way, in that they use chopped air to produce sound. The horns in that recording work on diaphragms, I think.
I guess I'm not the only one here who thinks that those horns actually sound scary!

[kanazo]

Found picture of one of these:


and another video of the "Kockum KTG-9"

http://www.youtube.com/watch?v=tYqMpzNaxBw


So they're basically just a bunch of airhorns tuned to quasi-scale that sound alternatively?

[SirenMadness]

They are air-horns by the looks of the housings behind the horn-throats. That circular casing underneath the horns is probably just there to protect a possible valve that redirects the air across the horn array; only one horn is hear to sound at a time. Also notice as to how the low frequency almost distorts the camera's microphone, while the high frequency just doesn't seem loud enough!

[Corey Hudson]

These seem to be the same.