MEI Customisation

Hi Zoltan, All,

> Tido's recently published MEI customization 
> <http://tido.github.io/mei-customization/> sparked a lively discussion...
and
> For more information on MEI Go! please keep an eye on the MEI-L 
> mailing list for updates 
> <https://lists.uni-paderborn.de/pipermail/mei-l/2016/001796.html> and 
> discussions. While it may not be the solution that the Community Group 
> is looking for, I would like to draw attention to this effort as point 
> of reference.

I joined the MEI-L mailing list yesterday.
MEI customization <http://tido.github.io/mei-customization/> says
> *We hope that this customisation can also be the starting point for a 
> common basic MEI customisation* to be shared between several projects 
> in future. We welcome comments and suggestions through GitHub issues.
I've decidedto post my comments and suggestions (questions actually) 
here, rather than on GitHub. Please repost there and/or to MEI-L if you 
think that's a good idea.

I'm a beginner with MEI customisation, and need some help:

Briefly: My problem with current encodings of CWMN is that they all 
assume that duration symbols have fixed meanings in a score, and that 
measures therefore "add up" at the symbol level. This ignores the 
performance practice tradition that is always associated with any 
humanly readable notation. In Mozart, for example, the last quaver under 
a slur is never played in the same way as the first. Ignoring 
performance practice traditions goes back at least to the invention of 
the metronome in the 19th century. I'm old enough to remember how awful 
the first computer renditions of Bach sounded in the early 1980s...
I also think that the famous collapse around 1900 had more to do with 
the disintegration of fixed tempi, than with the exhaustion of harmonic 
possibilities. The notation collapsed because the conventions make no 
sense in the absence of humanly perceptible tempo.

Whether this analysis is correct or not is, however, immaterial. :-)

I want to make an MEI customisation that uses most of the symbols that 
are used by CWMN, but without assuming tempo. If there is no tempo, then 
neither tuplets nor grace-notes make sense. It should also be possible 
for the description of /more than one/ temporal instantiation to be 
stored inside the XML elements that represent the score's graphics.
I think that CWMN (as defined by both MusicXML and your project) could 
be regarded as a superset of such a customisation. If the /default/ 
temporal realisation of such a score defined all the duration symbols to 
have fixed meanings, then <measures> could be made to add up at the 
symbol level by adding tuplet symbols (as annotations) and turning some 
notes into grace-notes.

One advantage of having a tempo-less customisation would be that 
lossless transcriptions of recordings can be made, without going through 
"quantisation". I /compose/ with milliseconds...

So my initial questions are:
1. Can <measure> elements be redefined so that they do not have to add 
up at the symbol level? The different <layer>s in the measure must 
however add up in real time (milliseconds) in any one temporal 
realisation stored in the score.
2. Can you imagine such a hierarchy of customisations? I'm also thinking 
of the container hierarchy that could become part of the W3C standard 
for describing /any /polyphonic music notation.

All the best,
James

-- 
http://james-ingram-act-two.de
https://github.com/notator