mtnhi7 Brings up some excellent points about whistles and horn sounds on Southern Pacific steam locomotives.
1) In general, ONLY the GS Class 4-8-4 passenger locomotives, NOT including the former Cotton Belt 4-8-4s, had the deep "steamboat" Hancock step-top whistles.
2) The whistles on the GS Class steam locomotives where air operated and NOT "playable" by the Engineer. The Engineer only had a small brass lever, which was pushed DOWN in order to blow the steam whistle.
3) Those SP steam locomotives equipped with the big Leslie Typhon air horn, also had a small brass lever for the Engineer's use when blowing the horn. Since the air horns were mounted way up front, and pointed directly forward, the sound carried much further forward than that of the steam whistle, which was mounted just forward of the cab in the skyline casing. Thus the Engineers pretty much ONLY used the air horns for grade crossing warnings, whistle the steam whistle was used for crew signals, i.e. calling out or calling in the Flagman, for example.
4) The air compressor direct exhaust of the spent steam, is one of the MOST characteristic sounds of ANY of the SP cab-forward class locomotives. Luckily, both Lionel and MTH seem to have gotten THAT pretty close in their respective sound packages.
