Interesting observation. All I can think of is that the blue / checked indicators are any transposition that could be appropriate with the settings as they are. For example, try clicking on Soprano Sax. Immediately, several things change: Trumpet and Clarinet (although only a Bb clarinet and not an A clarinet) are also highlighted, as well as the transpose=+2 in both the list below, and in the little space to the right of the key signature that was blank. Same for Guitar and Bass, which each sound an octave lower than written. However, Alto Sax and Bari Sax are both Eb instruments, but they have different numbers because alto is in a register an octave higher, so why isn't this handled the same as bass/guitar? Hint: because of Preferences, Channels, bass -1.

Trombone, despite being a Bb instrument in terms of the tubing fundamental harmonic series, is notated in concert pitch, so it shows with piano as standard concert pitch, no transposition. No other 'band' instrument that is included in the list is notated in concert pitch.

Now, does it help to display transposition options in this way, or confuse? I leave that to others. I had not even noticed it did this until you pointed it out; I just chose the transposition I wanted and didn't look further. And you're right, you can't change it. What USED to annoy me, until I requested it, was the fact there was no indication a transposition was in effect. As someone who plays instruments in many keys, including several trumpets that are not in Bb, this used to get quite confusing.

Thanks for a fun-filled few minutes. Hope that helped you. Or at least, perhaps what I wrote might someday help someone. grin

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