Italian siren

[Daniel]

Apparently some Italian communities test their sirens daily. This sounds like a 12 port siren (on 50 Hz.)

http://www.youtube.com/watch?v=EmybxZB-kyI

[orestis]

That's a rare recording!

Here's a brochure listing currently produced sirens in Italy by "LA SONORA" ( = The Loud One )
http://www.lasonora.it/Media/Pdf_PagGB/I_Cat_GB.pdf

And some photos of old Italian models

http://mariotedeschini.blog.kataweb.it/ ... antiaereo/

http://members.fortunecity.com/vascello/reportage4.html

I can't explain though, how these street-light shaped sirens work! Any ideas? All I can say is that they are definitely unique!

[bigloudnoise]

My guess on those "street-light style" sirens is that the sound is emitted downward, then deflected outward by the cone-shaped part beneath it. Similar in concept to a Thunderbeam, but in omnidirectional form.

[Daniel]

Thanks, Orestis!

In examining the historical La Sonora photo, it doesn't look like a traditional motor and rotor could fit in the upper section, though it could possibly be underneath the lower shield. Perhaps this is actually a speaker or electromagnetic horn. There is also a vehicle siren recently made (in Italy, I believe) in which air enters the center of the rotor at the front of the siren, like most sirens, but the ports face forward rather than at the sides. Perhaps this siren works like that one.

[orestis]

These sirens were installed before WWII.

Have a look at this close-up http://www.flickr.com/photos/paolino_foto/2207669348/

Maybe is just a horn, as you said Daniel... But the only known horn sirens in Europe are in Sweden and Norway perhaps.

Notice these tubular brackets holding the deflector, they look almost decorative, the whole thing looks like a baroque lamp!

It's a mystery. Hopefully we are going to find a sound or video file.

[orestis]

Mystery solved. The siren in question is indeed an electromagnetic horn: http://www.youtube.com/watch?v=Kef2TLXJ ... re=related.

Also I have found a web page of extreme interest about Italian sirens: http://www.bunkerdiroma.it/13sirene.html

And the best part (of the page) : 1941 "La Sonora" catalog (!) http://www.bunkerdiroma.it/documenti/ca ... sonora.pdf
Everything you always wanted to know about Italian sirens but were afraid to ask.

[SirenMadness]

The one in the very first video almost sounds like an HOR.

Also, how old are those omnidirectional horns? It seems like the Italians figured out the crude concept of a Modulator-like siren before the guys at Federal thought it up!

[Mantis]

Those horns are some of the coolest-looking things I've yet seen!

[ver tum]

That electromagnetic horn sounds like it would carry a long way. Almost sounds like an air horn in the distance.

[Daniel]

Those horns sound exactly like the electronic fog signals found throughout the Pacific coast of the United States.