I live In Canada and travel to the USA frequently. I have never heard of a white noise alarm. In fact if I heard it, I probably wouldn't even look up from what I'm doing. It just sounds like air brakes letting go.,(reply>), @Phil I hear them all the time, most semi trucks use them quite frequently, I live in Ohio, midwestern US, losts of semis, like everywhere, id say about 10-20% of total traffic, especially near the highways(we have 3 major interstates that run through my area.),(reply>), @Thread Bomb All reverb is environmental. Without an environment for sound to bounce off, there is no reverb. Just thought I'd be That guy 😅,(reply>), @Phil I feel they could have chosen something that's more like a mixture of the two, honestly. Incorporate that noisy isn't-going-to-bounce-off-walls texture to the sound, but make it perhaps a little more monotone. (Something like pink noise, maybe (except probably not pink noise itself)),(reply>), @How did I get subscribed to this channel? if I don't go with the bus and work at school or office, I don't hear air brakes.,(reply>), Try not to get eaten by a quacking tiger, Phil!