Instrument change causes wrong key signature

• Mar 27, 2020 - 14:41
Reported version
S3 - Major
GitHub issue

Instrument_Change_Bug.mscz If you use "change instrument" to change to a differently transposing Instrument the and press the "concert pitch" button it treats the new instrument like the original and messes up the key signature.
You can temporarily get around this by deleting the key signature but it messes up whenever you click the concert pitch button


This also happens when you change to a differently transposing Instrument. If you switch to soprano sax the concert pitch shows one sharp when there should be none

My guess is that whatever is going here is unique to changes that occur on the very first measure, which would be an unusual case. Normally if you wish to change the instrument from the beginning, you'd simply use staff properties.

A possibly related issue is that when inserting an instrument change that involves a transposition change, you actually need to add the new key signature manually (with Ctrl to limit it to this staff). I suspect that is the solution here, too, you need to add the key signature manually.

If this is an excerpt from a real world score, attaching a larger excerpt might help understand and assist better.

In reply to by Marc Sabatella

The main reason why you would want to have an instrument change at the start of a score is for big band sax sections where, for example, the alto 1 player would start on flute or soprano sax. You wouldn't call the part "flute" you would still call it alto 1. If you have an instrument change in the middle of a score this gets fixed though.

True enough. But it should still work to change the instrument to flute, then just make sure the staff name is set manually to alto sax. So I think that's still a valid workaround. Again, it would be good to see something like a real world use case to understand better what is really going on here.

Hi, I'm using Musesscore 4 (.2.1.2 ) and this bug is still present. Am I right? When changing from an transposing intrument to another and then back to the original one, Musescore looses the pitch information.

Pitch info isn't lost, but the key signature is not updated properly. That's already reported on GitHub - Workaround is to toggle concert pitch on and back off.

If you are seeing something else, probably best to first ask for help on the support forum to be sure it isn't something corrupt in the score itself. but if others can confirm it's a bug and not the same as the one already reported, then by all means, it will make sense to open a new issue on GitHub.