If anyone could send me a recording of one, I can run it through an FFT and tell you the exact frequency.

Wow, great info! I never would have found those details without your help. Thanks!

CrazyCalvinWilliams wrote: ↑

Sun Aug 13, 2017 6:55 pm

I don't know what that is, but I want to know and I want to buy one.

You and me both!

This video from Stonington, IL is one of my all-time favorites. How could anyone not love this ambience?
https://youtu.be/KZL4lrLQ4EA

I was reading about the recent protests in Charlottesville, and I came across an interesting picture. Does anybody know what this police officer is holding? And perhaps who the manufacturer might be?

No, it's single tone, so either a 3V8(H), 7V8(B) or 10V. I am extremely impressed by your ability to identify this one from nothing more than a terrible audio recording! But first...I finally found out why I keep hearing this siren at my house. It's actually located at a dam about a mile away from ...

I went to Sentry's website, and I downloaded their sample sound files for the 10V and the 10V2T. Lo and behold, the low frequencies in both cases are around 469-472 Hz, rather than the published value of 460 Hz. This matches perfectly to what I'm hearing at my house. Also, the 10V and the 10VT2 look...

No, it's single tone, so either a 3V8(H), 7V8(B) or 10V. You guys have been very helpful! I'm starting to wonder if this really is a single-tone siren, or not. I went to Sentry's webpage, and I learned that their two-tone sirens have tones at 460 & 920 Hz. This means that the high tone is exact...

Could you possibly upload the audio? The siren is very faint (that's why I'm having so much trouble finding it). So you can barely hear it in the recording, unless you crank the volume WAY up. And I hit "record" just before the spool-down started. But for what it's worth, here is the reco...

The tone that persists in you recording is more than likely reverb from a hill or some other structure that the sound can bounce off of. Yeah, I initially had the same thought. But if this truly is an echo that I'm picking up, then I would expect the same phenomenon to show up during the spool-down...