Talk:MODMOS scale

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Should we invent a new term to distinguish between these types of scales?

At the moment, this article says the following:

"In theory, although numerous options exist for the choice of chromatic alteration, the standard is alteration by the MOS's chroma, where the chroma is the difference between any pair of intervals sharing the same interval class. This choice of chromatic alteration interval is so fundamental to the structure of these scales that the term MODMOS, in its main sense, is generally interpreted as referring to only those scales being altered by this interval in particular. In the exposition below, we give a formal treatment of MODMOS's that looks only at chroma-altered scales. These scales are distinguished by the sense that they are epimorphic, and hence of special musical interest. However, alterations by other intervals may also be useful."

I wonder if maybe MODMOS should only refer to scales that are altered by chromas, and that some new, separate term should be invented to describe scales that are altered by another interval?

Maybe the term could something like "NSMODMOS" (non-strict modified moment of symmetry)? (Credit to Paul Erlich for coming up with that term during a Facebook conversation today :) )

--BudjarnLambeth (talk) 01:05, 12 January 2024 (UTC)

I worry that "non-strict" MODMOS would, maybe paradoxically, have a stricter threshold of recognizability, i.e. altering a MOS by something other than a chroma might increase the likelihood that it isn't recognized by the listener as a variant of the original MOS. It's only an hypothesis, though. The article already talks a bit about the existence of extreme cases, but there's no clear example, so here's one for the sake of this explanation: 12edo's ultrahard onyx MOS, 0 1 2 3 4 5 6 (12), can technically also be called a MODMOS of diatonic Locrian b3 bb4 bb5 bbb6 bbbb7. If you add on top of that the possibility of altering by any interval, not just the moschroma, then you're effectively calling every 7-tone scale a MODMOS of any given 7-tone MOS, and I don't think it's a useful category, unless you work systematically with a sort of "alteration measure" to keep track of scales that deviate too much from the MOS to rank them from most similar to least similar, and I don't expect such a measure to be perfect. I suppose one could make the point that extreme cases don't have to matter, and lightly altered cases could still be interesting. In that case, I'm not sure if NSMODMOS is a pretty term I'd like to use for such scales.
If it were up to me, MODMOS scales would be called "altered MOS scales", reusing the existing music theory term for "altered chord" (although altered scale is something specific, apparently?), and what's currently proposed as NSMODMOS scales, I would call "inflected MOS scales", coming from the idea that an "inflection" is similar to an alteration, but generally less strict and more contextual. Kite has recently made such a distinction between accidentals and inflections, as can be seen on the Arrow page for example. --Fredg999 (talk) 03:39, 12 January 2024 (UTC)
Thank you for sharing your thoughts on this, it is a big help :)
The MODMOS article as it stands right now reads "although numerous options exist for the choice of chromatic alteration, the standard is alteration by the MOS's chroma", which means that as it stands right now, those infinite options are already available, and they are included within MODMOS.
So the problem already exists.
What I am mainly hoping we can do, is contain the problem by giving that infinite field of other alterations its own separate term, so that they can muddy that term, instead of muddying the term "MODMOS" itself.
Within that infinite field, we can define various subtypes: MOSes altered by step sizes from the MOS itself, MOSes altered by the chroma of a different MOS, MOSes altered by JI intervals, etc.
But the first step, I feel, is to wall it off from MODMOS, to contain the problem.
I like the term inflected MOS. Should we have an abbreviation like IMOS or INFMOS, or should we just call it inflected MOS with no abbreviation? I'm happy either way.
--BudjarnLambeth (talk) 04:16, 12 January 2024 (UTC)
I have created the page now. I decided to go with inflected MOS as the name. Thank you for the name :)
--BudjarnLambeth (talk) 06:15, 14 January 2024 (UTC)