Marvel: Difference between revisions

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Tunings: it has occurred to me that overtempering obviously means tuning prime 7 flat (tempering 3 and 5 so much that the targeted 7 goes over the line), so this entire "12edo is the only overtempered small edo tuning" narrative is also wrong
Godtone (talk | contribs)
m simpler intervals have less tuning fidelity; this isnt a matter of opinion, it's an inevitable mathematical truth. odd 25 is a reasonable target for marvel which 53edo already tempers about as much as can be reasonable; shouldnt more of the lattice be captured? also, 225/224 is larger than the step size of these edos so the inconsistency should be cautioned
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== Tunings ==
== Tunings ==
In the 7-limit, the optimal way such as that taken by [[TE]] and derivatives to close out the comma 225/224 is to tune primes 3 and 5 flat, and 2 and 7 sharp. If we tune the octave pure, it leaves prime 7 the only variable to be sharp. This indicates that the supermajor second [[~]][[8/7]] should be flat (towards [[~]][[256/225]]), the subminor third [[~]][[7/6]] be sharp (towards [[~]][[75/64]]), the supermajor third [[~]][[9/7]] be flat (towards [[~]][[32/25]]) and the tritone [[~]][[7/5]] be sharp (towards [[~]][[45/32]]), such that every [[7-limit]] [[9-odd-limit]] interval is tuned between itself and the [[5-limit]] interpretation it is separated from by [[225/224]]. If we take these as hard constraints, then [[53edo]] and [[84edo]] are the smallest edo tunings to satify them, but if overtempering is allowed, many smaller edos are possible, such as [[31edo|31-]] and [[41edo]]. Interestingly, [[72edo]] is too overtempered to satisfy some of these constraints, whereas 53edo though satisfying these constraints is obviously undertempered, tuning the intervals closer to the more complex [[5-limit]] interpretations despite that the very point of marvel is to use these intervals for 7-limit consonances. [[84edo]], another superset of 12edo, is an interesting edo to look at. Going up to larger edos, [[166edo|166-]], [[178edo|178-]], [[197edo|197-]], and [[240edo]] are all great choices with different intonational characteristics.  
In the 7-limit, the optimal way such as that taken by [[TE]] and derivatives to close out the comma 225/224 is to tune primes 3 and 5 flat, and 2 and 7 sharp. If we tune the octave pure, it leaves prime 7 the only variable to be sharp. This indicates that the supermajor second [[~]][[8/7]] should be flat (towards [[~]][[256/225]]), the subminor third [[~]][[7/6]] be sharp (towards [[~]][[75/64]]), the supermajor third [[~]][[9/7]] be flat (towards [[~]][[32/25]]) and the tritone [[~]][[7/5]] be sharp (towards [[~]][[45/32]]), such that every [[7-limit]] [[9-odd-limit]] interval is tuned between itself and the [[5-limit]] interpretation it is separated from by [[225/224]]. If we take these as hard constraints, then [[53edo]] and [[84edo]] are the smallest edo tunings to satify them, but if overtempering is allowed, many smaller edos are possible, such as [[31edo|31-]] and [[41edo]]. Interestingly, [[72edo]] is too overtempered to satisfy some of these constraints, whereas 53edo though satisfying these constraints tempers in favor of tuning the intervals closer to the more complex [[5-limit]] interpretations, though because of their comparative simplicity (and thus lesser tuning fidelity), the 7-limit consonances of the 9-odd-limit still clearly work so that 53edo is [[consistent to distance]] 2 in the 9-odd-limit if we exclude 7/5 and 10/7 which are the most damaged. [[84edo]], another superset of 12edo, is an interesting edo to look at for its high performance in large odd-limits. Going up to larger edos, [[166edo|166-]], [[178edo|178-]], [[197edo|197-]], and [[240edo]] are all great choices with different intonational characteristics, though note that inconsistencies may often arise in the representation of the 7-limit lattice because [[225/224]] is itself larger than the size of the step of any of these edos.


The marvel extension [[hecate]] has the no-17's [[19-limit]] as its subgroup, and tridecimal marvel, the extension chosen by [[Gene Ward Smith]], is in the 13-limit. They merge in the rank-2 temperament [[catakleismic]], which can be conceptualized as accepting both rank-3 marvel structures simultaneously. One such tuning is excellently given by [[125edo]]. If we are looking for a small edo tuning instead, 53edo and 72edo are also reasonable edo tunings for the full no-17's 19-limit catakleismic, though in 53edo the 11 and 19 are a little off and in 72edo the 13 and 19 are a little off instead; 72edo is positioned better as a full [[17-limit]] marvel system while 53edo is positioned better as a (potentially no-11's) [[13-limit]] marvel system. If we focus on the 11-limit of undecimal marvel (discarding the mapping of 13), 31edo and 41edo are the smallest to clearly succeed, though many accept 41edo's mapping of [[~]][[13/8]] to the neutral sixth and some accept that mapping for 31edo as contextually usable too.
The marvel extension [[hecate]] has the no-17's [[19-limit]] as its subgroup, and tridecimal marvel, the extension chosen by [[Gene Ward Smith]], is in the 13-limit. They merge in the rank-2 temperament [[catakleismic]], which can be conceptualized as accepting both rank-3 marvel structures simultaneously. One such tuning is excellently given by [[125edo]]. If we are looking for a small edo tuning instead, 53edo and 72edo are also reasonable edo tunings for the full no-17's 19-limit catakleismic, though in 53edo the 11 and 19 are a little off and in 72edo the 13 and 19 are a little off instead; 72edo is positioned better as a full [[17-limit]] marvel system while 53edo is positioned better as a (potentially no-11's) [[13-limit]] marvel system. If we focus on the 11-limit of undecimal marvel (discarding the mapping of 13), 31edo and 41edo are the smallest to clearly succeed, though many accept 41edo's mapping of [[~]][[13/8]] to the neutral sixth and some accept that mapping for 31edo as contextually usable too.

Revision as of 21:23, 15 January 2025

Marvel is the rank-3 temperament tempering out 225/224, the marvel comma. It has a canonical 11-limit extension adding 385/384 and 540/539 to the comma list.

The temperament was named by Gene Ward Smith in 2002–2003, when the 11-limit version was found first[1][2]. Gene carried it to the 7-limit restriction in 2004[3].

Extending marvel to the 13-limit is not as obvious. While Gene has chosen 351/350 as the canonical extension, hecate, tempering out 325/324 and 729/728, arguably makes more sense as it is closer in tuning[4]. Hecate has a natural extension to the no-17 19-limit, by tempering out 400/399 and 513/512.

See Marvel family #Marvel for technical data.

Interval lattice

Notation

Marvel can be notated the same as 5-limit just intonation since they share the same lattice structure. One way to do this is to take the conventional circle-of-fifths notation with an additional module of accidentals for the 81/80 comma. In this system, 5/4 is a major third, 7/4 an augmented sixth, and 11/8 a double diminished 5th.

Marvel/hecate nomenclature
for selected intervals
Ratio Nominal Example
3/2 Perfect fifth C-G
5/4 Down major third C-vE
7/4 Dudaugmented sixth C-vvA#
11/8 Trup double-diminished fifth C-^3Gbb
13/8 Dup minor sixth C-^^Ab
19/16 Minor third C-Eb

Alternatively, it can be notated the same as full prime-limit just intonation, with a distinct accidental pair for each prime. That makes some intervals more intuitive, at the cost of hiding the structure of marvel tempering. For example, it is customary of the 5/4 to be a major third, and 7/4 to be a minor seventh. As a result, the fact that the 14/9 is a stack of two 5/4's is not revealed, and the related chords can be less convenient.

Chords

Marvel enables essentially tempered chords of marvel, keenanismic, swetismic, and undecimal marvel. Extending the temperament to the 13-limit through 325/324, resulting in hecate, enables chords of marveltwin and squbemic. Hecate hexad is a chord peculiar to this temperament.

Alternative 11-limit extensions give different sets of chords. One notable example, tempering out 441/440, enables prodigy chords.

Scales

Marvel hobbit scales

Undecimal marvel hobbit scales

Other marvel scales

Tunings

In the 7-limit, the optimal way such as that taken by TE and derivatives to close out the comma 225/224 is to tune primes 3 and 5 flat, and 2 and 7 sharp. If we tune the octave pure, it leaves prime 7 the only variable to be sharp. This indicates that the supermajor second ~8/7 should be flat (towards ~256/225), the subminor third ~7/6 be sharp (towards ~75/64), the supermajor third ~9/7 be flat (towards ~32/25) and the tritone ~7/5 be sharp (towards ~45/32), such that every 7-limit 9-odd-limit interval is tuned between itself and the 5-limit interpretation it is separated from by 225/224. If we take these as hard constraints, then 53edo and 84edo are the smallest edo tunings to satify them, but if overtempering is allowed, many smaller edos are possible, such as 31- and 41edo. Interestingly, 72edo is too overtempered to satisfy some of these constraints, whereas 53edo though satisfying these constraints tempers in favor of tuning the intervals closer to the more complex 5-limit interpretations, though because of their comparative simplicity (and thus lesser tuning fidelity), the 7-limit consonances of the 9-odd-limit still clearly work so that 53edo is consistent to distance 2 in the 9-odd-limit if we exclude 7/5 and 10/7 which are the most damaged. 84edo, another superset of 12edo, is an interesting edo to look at for its high performance in large odd-limits. Going up to larger edos, 166-, 178-, 197-, and 240edo are all great choices with different intonational characteristics, though note that inconsistencies may often arise in the representation of the 7-limit lattice because 225/224 is itself larger than the size of the step of any of these edos.

The marvel extension hecate has the no-17's 19-limit as its subgroup, and tridecimal marvel, the extension chosen by Gene Ward Smith, is in the 13-limit. They merge in the rank-2 temperament catakleismic, which can be conceptualized as accepting both rank-3 marvel structures simultaneously. One such tuning is excellently given by 125edo. If we are looking for a small edo tuning instead, 53edo and 72edo are also reasonable edo tunings for the full no-17's 19-limit catakleismic, though in 53edo the 11 and 19 are a little off and in 72edo the 13 and 19 are a little off instead; 72edo is positioned better as a full 17-limit marvel system while 53edo is positioned better as a (potentially no-11's) 13-limit marvel system. If we focus on the 11-limit of undecimal marvel (discarding the mapping of 13), 31edo and 41edo are the smallest to clearly succeed, though many accept 41edo's mapping of ~13/8 to the neutral sixth and some accept that mapping for 31edo as contextually usable too.

Tuning spectrum

This spectrum assumes pure 2 and 7.

Eigenmonzo
(Unchanged-interval)
Fifth
(¢)
Major
Third (¢)
Comments
5/4 698.099 386.314
6/5 700.027 384.386 7-odd-limit minimax
15/11 700.351 384.062
10/9 700.670 383.743 9-odd-limit minimax
11/10 700.885 383.528
15/13 700.916 383.497 15-odd-limit hecate minimax
13/10 701.065 383.348 13-odd-limit hecate minimax
13/11 701.199 383.214
18/13 701.361 383.052
13/12 701.480 382.933
16/13 701.559 382.854
4/3 701.955 382.458
14/11 702.278 382.135
11/8 702.278 382.135
12/11 702.602 381.811

Music

Billy Stiltner
Chris Vaisvil

See also

Notes