Over the past several years I have been installing a theatre pipe organ in our home. One of the features of these instruments is the sound effects used in accompanying silent movies. I have slowly been adding these effects, or toys, over the past several months.
This past week I built and installed a train whistle. I researched whistle pitches and selected several samples to try. I was not satisfied with any of the pitch sequences that I found. In the end I came up with my own three chime whistle. I liked the sound of the three pitches and constructed the pipes accordingly. I know it would have sounded a whole lot better if I was using steam instead of air, but this thing is in a house and is plenty loud as it is.
Here is a short video of the whistle. Sorry about the quality. I was trying to do three things at once, which is about two and a half more than I am capable of.