Transposing

I believe the easiest was it to just change instrument to Bb Clarinette, right-click on staff -> staff properties -> change instrument

Yes, don't use the Transpose command at all. Make sure your clarinet part has been correctly set up for the clarinet - either by choosing Bb Clarinet from the instrument list when you create the score, or changing it after the fact as Jo-Jo describes. Once the piece has properly been created, the only thing you need is the Concert Pitch toggle button at top left of your score. When concert pitch is on, your clarinet part will display at concert (sounding) pitch, and notes you enter should also be at that pitch. Then, simply click that button to turn Concert Pitch *off*, and your clarinet part is *automatically* transposed to display at written pitch. You can go hack and forth between the modes as simply as pressing that button. It's all you need.

Basically the Concert Pitch is the easy way to write scores with many transposed instruments and have no headache. When it's on, all the instruments are written in the same scale (for you in C). It's much easier and secure way to avoid mistakes. So, you just copy the parts you like, exactly as they are. After finishing the score, you click again the button and everything is transposed (what the musicians play). Fast and simple.

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