It sure sounds like it, and that looks like a very Chicago balcony the recorder is on. :D Fucking alien whale song sirens….
The thing that gets to me most about this siren is that it wavers with no cadence. That’s not a Doppler effect due to the recorder moving, nor is it due to the source moving, so what the fuck is going on here?
I’ve only ever heard the siren while living downtown, so I can’t be sure, but there’s a theory that it’s technically a normal siren but due to the density and height of the buildings, there’s an echo effect that causes the siren to oscillate that way. I’m not an….audio scientist, so I don’t know if that’s even possible or likely. It seems unlikely given no other dense urban area’s alarm sounds like this, but most dense urban areas aren’t focused like a lens around a lake. If the siren is out at the end of Navy Pier, which is way out in the lake, it could be bouncing off the facade of the lakefront buildings, I suppose.
If you’re interested, my audio recording of the siren from the fairly architecturally dense South Loop is here. It was recorded on my phone through an open window in my apartment; my apartment looks north, but the building I’m in has an unobstructed view of the lake to the east.
