RE: GDP glossary question: complex meters

[Palmer, Ralph]

Hi, Kurt -

When I brought up "my" definition, it certainly was not intended to be
exclusive (as in the only definition). I was trying to point out that
there was an alternative meaning to polymeter. I have no easy answer to
the problem(s), especially since I think polymeter or complex meter can
refer to more than time signatures - either initial or subsequent. Are
the layered patterns in some West African drumming considered to be
polymeter, or is that polyrhythm? I think western music's recent and
rapid exposure to a lot of different rhythmic structures, notations, and
possibilities have helped create a confusing set of terminologies whose
definitions haven't settled down yet.

Ralph

-----Original Message-----
From: Kurt Kroon [mailto:address@hidden 
Sent: Tuesday, February 26, 2008 1:40 AM
To: Mats Bengtsson; Palmer, Ralph; Graham Percival; Till Rettig; Ole
Schmidt; Valentin Villenave
Cc: lilypond-user Mailinglist
Subject: GDP glossary question: complex meters

BACKGROUND

We now have a number of different terms to refer to several closely
related
concepts:

* polymeter
* polymetric time signature
* double time signature
* compound time signature

(
Elsewhere -- just to add them to the mix -- I've seen:
* mixed meter / mixed time signatures
* additive time signatures
* alternating time signatures
)

Last month, we (meaning "y'all") had a discussion about the "one true
polymeter": Valentin's definition (group A), where different meters are
used
_simultaneously_ on different staves; and Ralph's definition (group B),
with
regular alternation between different meters.  [I'm not interested in
resolving that discussion, just standardizing the terminology we use.]

LilyPond handles group A quite easily, by simply "moving the
Timing_translator to the Staff context".

Group B, due to its polymorphous nature (and resemblance to Hydra), is
handled unevenly.

* LilyPond deals with mixed meters (where meter alternates without a
specific pattern) pretty well
* Double -- aka "alternating" -- time signatures "are not supported
explicitly, but they can be faked" [NR 1.2.3.4].
* Additive meters are covered in a snippet ... named
compound-time-signatures.ly (that's where I got 'compound time
signature)

(I'm not sure if one can extend this last one in LilyPond to more
complex
examples, like when the numerator is an additive expression, and the
denominator is a single digit, e.g. (3+2+3)/8.)

SO, MY QUESTION

How can we normalize the terminology?  Here are my thoughts on the
matter,
trying to distill this into a controlled lexicon --

* polymeter -- the most generic term
    * sequential polymeter -- Ralph's definition
        * regular
        * irregular
    * simultaneous polymeter -- Valentin's definition
        * regular and irregular (theoretically)

And here's what happens to the list of terms above:

* polymetric time signature
Deleted: although it implies sequential polymeter, it has too many
possible
interpretations to be useful.

* double time signature
* compound time signature
* additive time signatures
* alternating time signatures

Become "See also _sequential polymeter, regular_"

* mixed meter / mixed time signatures
Becomes "See also "sequential polymeter, irregular_"

So ... what are your thoughts?

Thanks!
Kurt