The Siren Board

I found this cool photo of Federal Sign & Signals soundproof test room. The description reads "Worlds loudest siren which is being tested in one of the worlds quietest rooms...... As a result this fibre glass-lined room, almost 100% soundproof, was built to test air raid warning devices..." The photo is dated 8/20/1955.

Awesome

I find it odd that it doesn't have the bars in the horn despite the fact the photo is from when jailbars were in production

I totally did not expect to see walls like that! This is just awesome!

Chicagosirenhunters wrote:I totally did not expect to see walls like that! This is just awesome!

yeah, "wedge" panels like that are common for anechoic chambers. Fiberglass can be used, but now it's more common to use rock wool for better low frequency attenuation. Plus rock wool doesn't itch like crazy if you get any on your skin.

I've been in several anechoic chambers in my career; it's really unnerving. There's no background noise, no reverberation, no echo. You can hear your heartbeat in your ears. Enough to drive you crazy if you're in there long enough.

nice find on that photo, she seems positively enamored with that Thunderbolt

That Thunderbolt said "I found a girl friend"
Anyways I saw a picture of an EOWS 612 in a room just like that it was in some sort of ad I think.

Jim Z wrote:nice find on that photo, she seems positively enamored with that Thunderbolt

Who says women can't be siren fans, too?

I imagine it must have been hard for siren freaks back in the day before the Internet was devised.

Had the distinct pleasure of visiting Federal for a siren training class in about 2007 or 2008. Got to go into the anechoic chamber; don't think it's the same one pictured; the one I was in was a cube about 15 ft. on a side, interior dimensions.

And yes, it was a weird sensation being in it, even with other people, because well, no echos. None. Zero. Anybody who has ever been in a snow fort is only about 2% of the way to what this was.

Imagine if that thing fired off while that lady was still on it...