This was posted on youtube by trainguyONR. I realize it's from Canada, but it was titled "The best train horn ever- ONR GP38-2 1805." I would have to agree, what a horn!
I have more to come from this guy, just asking permission. Some of his other films showcase horns that are simply inspirational. I'll try to get them posted ASAP. Check out his channel TrainGuyONR
I now have a desire to move to Canada!
Photo Credit Paul Lantz