Sorry about request, but I just had to... (it's should be easy to implement - and it could be a great use) It would be nice for learning transposing instruments to be able to transpose only a view, not a sound of a note. I'm a clarinet beginner. It's a transposing instrument ("E♭, sounding a minor third higher than written" via wikipedia).
What I do right now: (and it "works")
I'm running two instances of Piano Booster (with the same midi file), one with sound and one without. The one without sound is configured to "Transpose: -3". I start them both at once (by fast click to another instance ........ ).
I read scores from transposed one, but sound is from not transposed one... and it 'works'.
What i would like (I know, it's a free project - it's rude to "would like", please read this as "i'm begging you"):
Simple another box "instrument transposition", so the sound would be:
original note + transpose box
and view would show
original note + transpose box + instrument transposition box
brilliant it makes it much easer if you can compile from source. As I'll check in my changes into svn as source code for you to try out. By the way i just compile using the qt creator free version which works well on all platforms.
I'll add a box on the Song Details screen (available from the Song menu) with an instrument transpose option.
I could allow it work with rhythm tapping with the foot pedal of a piano, so it will wait until you tap your foot on each beat before playing/moving on to the next note.
Let me know how you get on with any audio2midi converter.