Cross-staffing between parts

[rpatters1]

It seems like the only cross-staffing that is possible is within a part. That seems restrictive to me. I can think of a number of use-cases for cross-staffing between parts. These include:

• multi-percussion scores, where one player is playing multiple instruments at the same time.
• contemporary scores that cross-staff chords and figurations across an entire ensemble.
• a piano score with a separate "effects" part, e.g., playing the cross beams with a mallet.

One could argue that the last case is not really multiple parts, but it is certainly a case that is outside the mainstream of how parts are scoped in the spec. It might be more flexible to permit it to be handled as multiple parts. It is unlikely, for example, that a Finale export could ever treat that case reliably as a single part, since Finale lacks a concept for multi-staff parts outside the canned mainstream examples we all know about.

One solution that comes to mind is simply to replace the optional note.staff with some kind of object that is part/staff. But there may be other, better ways to do it. Plus, I may have missed something in the spec or past discussions around this issue.

[adrianholovaty]

Interesting — thanks for bringing this up. Would you happen to have some images handy, to help make these examples a bit clearer?

Based on your description: this feels slightly more presentational than semantic, which makes me wonder whether it's a good fit for the MNX layouts system instead of being encoded directly in the note or event. It also seems fundamentally different from, say, grand-staff piano music.

[rpatters1]

I agree with your instinct that it is more a presentation, but it is also a much clearer notation of meaning if used judiciously.

Here is an example (in strings and also in percussion) from Ives Symphony 4 (p 57 of the score):

Here is an example from Crumb Black Angels:

Crumb uses this notation in various spots throughout Black Angels. In Start Child he frequently links all the parts in each instrument family with common stems and beams.

I believe this kind of thing is pretty common in contemporary multi-percussion parts, but I can't see to lay an example to hand. I've looked at a lot of contemporary scores in my day, but most were from libraries.

I don't much care for the idea of extending part.note either, because it seems to me that notes should only be in the parts they apply to, and extending part.note would break that rule.

[mscuthbert]

MusicXML's notion of multi-staff parts as being a single stream with notes assigned to staves (and backup, etc.) would make allowing multi-part beams and chords very difficult. My understanding is that in MNX it would be much less of a stretch to allow that. I'm in favor.

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(misc supporting notes and not-currently-proposed things that might someday be enabled by this change)

Here's the Crumb "Star Child" excerpt, which is otherwise more traditional than the Black Angels example of the same thing.

Nothing proposed though will allow for my favorite cross-staff beaming/chords example (from Corigliano string quartet; the other W3C chairs have seen me present this) where beamed chords begin simultaneously but slowly drift away from each other:

This kind of flexible model, btw could ultimately allow for something that occurs commonly in critical editions/urtext of sketchbooks etc.: a staff being used by one instrument for part of the system (like divisi celli split onto a staff above) and another instrument for another part of the same system (like divisi violas split onto the staff below). In every case that I've had to engrave this, I've just aligned two different stages as best I could to use the exact same space so that they look like one staff. (Like in this edition of Beethoven's sketchbooks I once did; though this is even worse: two different systems sharing the same middle staff:

)

[mscuthbert]

@rpatters1 wrote:

a piano score with a separate "effects" part, e.g., playing the cross beams with a mallet.

All still underdefined, I believe. MNX is not currently especially specific on what a part means:

The part object represents a set of measures which describe a single part within the score — generally corresponding to a single instrument.

Does a soprano who plays the triangle count as two parts or one? Or three cellos switch to viola da gamba... As far as I know, Dorico has the richest model for what is a player, and instrument, a section of players, a part, etc. and even with that there are still many corner cases that require tweaking ("I'll pretend I have a clarinet that can make a pizzicato violin sound, since it's the closest sound I have to a keyclick", etc.)

[rpatters1]

Personally, I am quite impressed and satisfied with the mnx concepts score -> layout -> part -> staff. I don't think it matters to the notation how many players play from the score. In Finale context, which is where I am most comfortable, part essentially means instrument. In fact, before ca. 2011 Finale did not have a concept of multi-staff instruments, and I'm pretty sure it was added for better musicxml compatibility with parts.

[mscuthbert]

I don't think it matters to the notation how many players play from the score.

Please remember that formats are also useful to playback systems and others. Notation engraving isn't the only use for encoded music.