Playing around with my Rock Band 3 Mustang MIDI Guitar Control [ which are an astonishing $48 these days!
http://www.amazon.com/Wireless-Mustang-PRO-Guitar-Controller-PlayStation-3/dp/B003RS1A7Y ] I noticed that something wasn't quite right. If I was really good at sight reading, I wouldn't need help ;-> but I finally realized that everything was off an octave. So to play the E at the top of the treble staff, I'd need to play the high E string at the 12th fret. That's not right. The way I cured it was to open the file "MidiEvent.h" and change:
int note() const {return m_note;}
to
int note() const {return m_note + 12;}
I don't know if there's a better way to do this, but it seems to work so far. Of course this will probably mess up your experience with MIDI keyboards. Compiling two executables seems like a workable solution for now.
It seems to me that "Piano" Booster was perhaps a premature name. I propose changing the name to "Music Booster". My next project will be to build a MIDI facsimile of a very complex weird antique instrument I own but don't want to abuse while I learn to play it. Anyway, thanks again for this great program and I hope this is useful to someone.