To reproduce: set up a test score, place a single note, place a 16th note duration grace note.
Expected: grace note that lasts a 16th note duration before the main note.
Result: grace note that lasts a 8th note duration before the main note.
Grace notes that follow a note do not play at all.
Comments
That is not how grace notes work. Appoggiaturas -(with no slash through stem) are meant to be played half the duration of the main note; acciaccaturas (with stem through slash) are meant to be played as fast possible. In neither case is the notated duration of the grace note itself actually relevant. See for example https://en.wikipedia.org/wiki/Ornament_(music)#Appoggiatura and https://en.wikipedia.org/wiki/Ornament_(music)#Acciaccatura. So the playback is correct.
It is true that grace notes after do not currently play back at all; that's already an open feature request for future consideration.
Mind to link to that open feature request for playback of grace note after? I searched but couldn't find it.
There are a number of related ones that touch on this, but maybe the "main" one is #13811: Select playback method of Grace Notes, Arpeggio & Glissando and Articulations & Ornaments. It links to a bunch of others.
"The long appoggiatura (as opposed to the short appoggiatura, the acciaccatura) is important melodically and often suspends the principal note by taking away the time-value of the appoggiatura prefixed to it..."
It says that generally they play for half, but not always.
Example:
https://i.imgur.com/o2Ute79.png
Why would they be noted as 32-length appoggiaturas if that didn't imply a difference in duration versus the standard?
They don't *need* to be notated using 32nd notes, but of course it's expected in some contexts (looks odd to have an quarter note appoggiatura into an eighth main note), so we provide options to provide the desired *look*.
It seems clear from context that your example doesn't show an appoggiatura at all; it shows an acciaccatura that happens to have been notated without the slash. Unfortunately, there has been little standardization of this notation, and indeed, certain publisher in certain periods of hsitory have used the slash-less grace note to mean acciaccatura. Most modern publishers would genrally notate that with the slash, but some choose to use older historical standards instead of more current ones. So what you really have here is a case of an acciaccatura that you would like to display *as if* it were an appoggiatura, if you for some reaosn want to emulate this particular edition rather than move to the more modern standard.
So someday, an option for customizing this would be ncie, and indeed, there is already a feature request for that. But again, the current behavior is *not* a bug; it is absolutely the correct default playback.
Eh, figured as much after I posted. I'm just trying to think; there was something I was working on that resulted in me posting this, because it did not sound right using the ordinary grace notes. I just forget what it was...
Oh, right, now I remember! Beethoven's 7th symphony, second movement.
https://i.imgur.com/LsbgM7L.png
Such grace notes come up a lot, and let me tell you; they are not played each as a third of the duration of the note. They're played in respect to a normal quarter note, giving them a shorter duration than what Musescore would normally put in. They're not acciaccaturas either; they're certainly played for longer than that. Maybe grace notes could disregard dotted note duration and assume an undotted note? If you listen to any recording of that song, I can guarantee that the grace notes are played for the same duration of the 16th notes that immediately follow the dotted quarter note, not longer.
Indeed, there are always exception, and different composers and in particular different editors will use different notations to mean the same thing, and the same notations to mean different things. So the request for customization is certain valid. The idea of ignoring dots when not in compound meter has come up before and is definitely worth considering as well, but that's very much a special case that doesn't address the basic fact that is little standardization here.
grace-notes-after have a proposed fix.
See SR https://github.com/musescore/MuseScore/pull/2757