The steamers we have sound great and the pitch goes up as I pull the 'lever' down. I feel that I have full control. On the several diesels we have (PA's, AC6000, Sharks, Geeps, & GE-U28c) the horn is 'reversed' in that it comes on 'high' and drops in pitch and volume as I lower the slider. It is difficult to hold a note most of the time
Your ear is correct. This is prototypical behavior. As the steam pressure increases, a whistle's pitch goes up. However, for a diesel air horn, who's oscillation is created by a flapping metal diaphragm, as air pressure increases, the pitch goes DOWN.
As far as holding a constant intensity, there is no difference in cab remote operation, a given thumb pressure on a CAB1L, or a particular lever position with a cab2 will always generate the same consistent result from a given sound set, regardless of steam vs. diesel. Of course, some whistles have more dramatic variation in sound, other less.
As to consonant vs. dissonant sounds within a single whistle, this too is prototypical. Different length chimes change pitch in different amounts. Therefore, the relationship between notes (in musical terms, the chord type - minor, major, diminished, etc) will change, as well as transpose) as a horn or whistle is played over its range.
Rudy Trubitt
Director of Audio
Lionel, LLC
