A Rare catch for me on the Alabama Gulfcoast Railroad, comes a ex Missouri & Wisconsin with a small freight train heading for the international Papermill at around 9:30pm.
ELS 501 has a cool horn that looks and sounds to me like a Nathan P5, but people have told me RS5T or Nathan M3 (which I know it can't be because when you look at the horn, it has five tubes):
Soo Line 4512 in ex-Milwaukee Road "Bandit" paint may look somewhat worse for wear, but it has a nice sounding horn that I've been told is a Prime 920/RS hybrid: