Jetro got a dPressure sensor for NXT, from Dexter Industries and immediately started to think, how this could be used into some type of innovative model/application.
Finally he came up with a playable electrical MINDSTORMS Trumpet.
Together with an old style pneumatic pump (a single inlet cylinder with return spring) he was able to turn pressure levels into harmonic tones [1, 2] coming out of the trumpet (NXT brick).
With 3 additional Touch Sensors he manged to find a way for lowering the pitch by 1, 2 or 3 semitones. Here through some software programing, instead of acting as a set of piston valves, like in the real trumpets.
Below you can see an image from the pump and touch sensor blocks, together with the dPressure sensor itself.
And more can be found at Jetro's flickr photostream.
I'm a bit heard of earing, but guess Jetro is mastering some classic, in his performance.
As almost every Sunday I use to feature one video here at TBs , I've been preparing this for this weekend. As a matter of coincidence, Jetro came with a post of his own at EB about this same contraption. Read it here.