Add Optional Text to Metronome and Dynamics Elements

[dougheyer]

A proposed change to the MusicXML metronome and dynamics elements (is it too late for 4.1?)

Add string type to schema definitions: <xs:element name="metronome" type="xs:string" minOccurs="0"> and <xs:element name="dynamics" type="xs:string" minOccurs="0">. This would allow the integration of "rit.", "accel.", "cresc.", "dim.", etc. terms with the existing metronome/dynamics elements . This change should require no changes to the current use of those elements, and it would give developers a better way to handle tempo and dynamics during MIDI playback. (You could also incorporate "dashes" as an optional (child) element for metronome , although this would affect current schema validation...) Maybe talk to the MuseScore team to see what they think about these changes--it might be a solution for some of the problems they (and their users) have had in this area.

[mdgood]

This seems unnecessary, as MusicXML already handles combinations of metronome marks, dynamics, lines, symbols, text, and more. These are represented using multiple <direction-type> elements within a single <direction> element. Elements like <metronome> and <dynamics> are children of the <direction-type> element. MIDI playback can be handled by using the <sound> element as an additional child of the <direction> element.

[mdgood]

If there is something specific that seems to not be covered by the current definition, could you please post a repertoire example? Thanks!

[dougheyer]

Well, I guess this applies to all repertoire. I am particularly concerned with the general handling of rit. and accel. during MIDI playback, especially MIDI streaming, although this concept could apply as well to cresc. and dim. when working with dynamics. Since rit. and accel. are logically extensions of "metronome" (tempo) metronome would be a convenient place for the user to display the text and have the program automatically produce a smooth transition to the next metronome setting in the music timeline--this in lieu of placing a series of metronome or sound objects, which is subject to a granularity "staircase" problem and can be a tedious effort. With the starting and ending metronome values the program can use an appropriate equation of a line/curve to modify the real time duration of each intervening MIDI event. When streaming, these gradual tempo changes can be applied with millisecond granularity. Yes, the schema already provides the data to accomplish this, but it seems to me that combining tempo-related text with the tempo-related metronome element and dynamics-related text with the dynamics-related dynamics element would be an easy change and would be intuitively easier for everybody to work with. It's just an idea. Maybe I'm missing something?

[mdgood]

MIDI 1.0 doesn't have smooth transitions between metronome settings. At some point you have to output all the appropriate tempo events to gradually change the speed. MusicXML reflects this with the <sound> element using the tempo attribute.

When you have 25 years worth of working software, much of which will never be updated, and a commitment to being an archival format, nothing that is incompatible with current behavior is an easy change.

[dougheyer]

OK., I relent. I've been watching the development of MusicXML since it was not much more than an XML representation of a MDI file. It has become not only a temporal, but also a spatial and acoustical database of music phenomena. Thanks for all the good work!