User:Ganaram inukshuk/Notes

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This page is for miscellaneous xen-related notes that I've written about but don't have an exact place elsewhere on the wiki (yet).

On the Origin of MOS Recursion

MOS Recursion and Replacement Rules 1 and 2

MOS recursion describes a set of properties that all moment-of-symmetry scales share that, among other things, allows us to create a few algorithms for determining whether an arbitrary scale of large and small steps has those properties.

The child scale of a MOS follows a distinct pattern in which the large step breaks up into the next large step and the next small step (in some order) and the small step becomes either the next large step or the next small step. As such, we can represent this as two sets of replacement rules:

  1. Replacement ruleset 1 (where L - s > s)
    • L -> Ls
    • s -> s
  2. Replacement ruleset 2 (where L - s < s)
    • L -> sL
    • s -> L

It should be noted that if the order of L's and s's is reversed (for example, L->sL and s->s for ruleset 1), the rulesets are still valid. The numbering of rulesets is also arbitrary. For explanation purposes, rulesets 1 and 2 and successive pairs of rulesets are denoted as though they were sisters of one another; this sistering process can be described with its own ruleset:

  • L->s
  • s->L

Replacement Rules 3 and 4

Applying ruleset 1 to itself n times produces ruleset 3, where L produces an L followed by n s's:

  • L->Lss...ss (n s's)
  • s->s

As such, applying ruleset 1 to itself n-1 times will result in L producing an L and n-1 s's. If ruleset 2 is applied to this, it creates ruleset 4, where L produces an s followed by n L's, the sister of ruleset 3:

  • L->sLL...LL (n L's)
  • s->L

Replacement Rules 5 and 6

Reversing the order of L's and s's of ruleset 2 produces this intermediate ruleset:

  • L->Ls
  • s->L

Applying ruleset 1 to the reversed form of ruleset 2 n times produces ruleset 5, where L produces an L followed by n+1 s's and s produces an L followed by n s's:

  • L->Lss...ss (n+1 s's)
  • s->Lss...s (n s's)

Applying ruleset 2 to ruleset 1 n times produces ruleset 6, the sister of ruleset 5 where L produces an s followed by n+1 L's and s produces an s followed by n times:

  • L->sLL...LL (n+1 L's)
  • s->sLL...L (n L's)

The final rulesets are as follows:

  1. Replacement ruleset 1
    • L -> Ls
    • s-> s
  2. Replacement ruleset 2
    • L -> sL
    • s -> L
  3. Replacement ruleset 3
    • L->Lss...ss (n s's)
    • s->s
  4. Replacement ruleset 4
    • L->sLL...LL (n L's)
    • s->L
  5. Replacement ruleset 5
    • L->Lss...ss (n+1 s's)
    • s->Lss...s (n s's)
  6. Replacement ruleset 6
    • L->sLL...LL (n+1 L's)
    • s->sLL...L (n L's)

On the Chunking Operation

The chunking operation is contingent on rulesets 5 and 6 since there must be two unique chunks whose string sizes differ by exactly one L or one s. Repeatedly applying these rules as reduction rules on a valid moment-of-symmetry scale will reduce the scale to a progenitor scale of either Ls or sL. The reduction rules can be denoted as such:

  • Reduction ruleset 5
    • Lss...ss (n+1 s's) -> L
    • Lss...s (n s's) -> s
  • Reduction ruleset 6
    • sLL...LL (n+1 L's) -> L
    • sLL...L (n L's) -> s

However, it may be the case that the reduced scale has only one L or one s, or that that the scale started out this way. In either case, rulesets 5 and 6 cannot be used, but rulesets 3 and 4 can be used instead:

  • Reduction ruleset 3
    • Lss...ss (n s's) -> L
    • s -> s
  • Reduction ruleset 4
    • L->sLL...LL (n L's) -> L
    • L -> s

For reduction ruleset 3, the entire scale except for one s is replaced with an L. For reduction ruleset 4, all but one L is replaced with an L with the remaining L replaced with an s. This can also be thought of using reduction ruleset 2 (sL -> L and L -> s) followed by reduction ruleset 3.

Using these rules as reduction rules allows for the scale to still be reduced back down to Ls or sL.

Since all MOSses must ultimately come from a pair of generators (represented in the progenitor scale as L and s), then this proves that if an arbitrary scale can be reduced to Ls or sL, then the scale itself must be a MOS.

Note that this only applies to single-period scales; for multi-period scales, such as LLsLsLLsLs, the rules must be applied individually to each period and the resulting progenitor scale will be either Ls or sL repeated multiple times, and it cannot be a mix of both Ls and sL.

On Modal Brightness and Numeric Encoding

Using Scale Codes to Sort by Modal Brightness

Modal brightness typically refers to how "bright" or "dark" the usual diatonic modes are (lydian, ionian, mixolydian, dorian, aeolian, phrygian, locrian). Since diatonic (5L 2s) is one of many moment-of-symmetry scales, the idea of modal brightness can be generalized using UDP notation.

For example, the seven modes of diatonic can be encoded as LLLsLLs, LLsLLLs, LLsLLsL, LsLLLsL, LsLLsLL, sLLLsLL, and sLLsLLL, whose UDP are 6|0, 5|1, 4|2, 3|3, 2|4, 1|5, and 0|6 respectively. The scale codes can be interpreted as binary numbers (L = 1 and s = 0), producing 1110110, 1101110, 1101101, 1011101, 1011011, 0111011, and 0110111. Doing this provides a mathematical way of understanding how modal brightness works, since larger binary values mean brighter scales.

Scale code Binary Decimal MOS UDP MOS name Mode name
LLLsLLs 1110110 118 5L 2s 6|0 Diatonic Lydian
LLsLLLs 1101110 110 5L 2s 5|1 Diatonic Ionian
LLsLLsL 1101101 109 5L 2s 4|2 Diatonic Mixolydian
LsLLLsL 1011101 93 5L 2s 3|3 Diatonic Dorian
LsLLsLL 1011011 91 5L 2s 2|4 Diatonic Aeolian
sLLLsLL 0111011 59 5L 2s 1|5 Diatonic Phrygian
sLLsLLL 0110111 55 5L 2s 0|6 Diatonic Locrian

Therefore, to produce the modes of a MOS in descending modal brightness, start with the scale code, produce all of its possible shifts, interpret them as binary numbers, and sort them in descending order. It should be noted that the characters "L" and "s", when sorted in lexicographic order (IE, alphabetical order), equivalently represent the binary representations in descending order, so the conversion to binary numbers is technically not necessary.

Side note: there is a concept known as "cyclic permutational order" that coincides with the notion of shifts, and the only reference to it anywhere on the wiki is this page on mavila temperament.

As an example, consider 3L 4s represented as sLsLsLs. Its six other shifts are LsLsLss, sLsLssL, LsLssLs, sLssLsL, LssLsLs, and ssLsLsL. Sorting them produces LsLsLss, LsLssLs, LssLsLs, sLsLsLs, sLsLssL, sLssLsL, and ssLsLsL, and are enumerated using UDP notation from 6|0 to 0|6 accordingly. Again, the binary representation (and decimal forms) gives an intuitive sense of what it means for a scale to be bright. As of writing, the article on 3L 4s is written using sLsLsLs (UDP 3|3) as the "default" mode, or the mode represented using middle C as the root (or TAMNAMS middle J); in comparison, the default mode for diatonic is ionian (UDP 5|1, or LLsLLLs). UDP notation gives a sense of how many modes are brighter or darker starting from the default mode, though these sortings (and thereby binary encodings) provide that sense without any notion of a "default" mode.

Scale code Binary Decimal MOS UDP MOS name Mode name
LsLsLss 1010100 84 3L 4s 6|0 Mosh Dril
LsLssLs 1010010 82 3L 4s 5|1 Mosh Gil
LssLsLs 1001010 74 3L 4s 4|2 Mosh Kleeth
sLsLsLs 0101010 42 3L 4s 3|3 Mosh Bish
sLsLssL 0101001 41 3L 4s 2|4 Mosh Fish
sLssLsL 0100101 37 3L 4s 1|5 Mosh Jwl
ssLsLsL 0010101 21 3L 4s 0|6 Mosh Led

Including the Modes of More than One MOS

As a curiosity, there are 128 possible 7-bit numbers (0000000 to 1111111) representing the unsigned integer values of 0 to 127. Among the 6 possible heptatonic MOSses (1L 6s, 2L 5s, 4L 3s, 3L 4s, 5L 2s, and 6L 1s), there are therefore 42 modes total. For our purposes, we include equiheptatonic (7 equal divisions of the octave) as being represented by both 0000000 and 1111111 (or simultaneously being both 0L 7s and 7L 0s) for a total of 43 (or 44) scales.

Though modal brightness makes more sense when thinking about the modes of a single MOS, this is how the modes of all six MOSses are ordered when sorted from highest binary encoding to smallest binary encoding:

Scale code Binary Decimal MOS UDP MOS name Mode name
LLLLLLL 1111111 127 7L 0s 0|0 Equiheptatonic Equiheptatonic
LLLLLLs 1111110 126 6L 1s 6|0 Archeotonic Ryonian
LLLLLsL 1111101 125 6L 1s 5|1 Archeotonic Karakalian
LLLLsLL 1111011 123 6L 1s 4|2 Archeotonic Lobonian
LLLsLLL 1110111 119 6L 1s 3|3 Archeotonic Horthathian
LLLsLLs 1110110 118 5L 2s 6|0 Diatonic Lydian
LLsLLLL 1101111 111 6L 1s 2|4 Archeotonic Oukranian
LLsLLLs 1101110 110 5L 2s 5|1 Diatonic Ionian
LLsLLsL 1101101 109 5L 2s 4|2 Diatonic Mixolydian
LLsLsLs 1101010 106 4L 3s 6|0 Smitonic Nerevarine
LsLLLLL 1011111 95 6L 1s 1|5 Archeotonic Tamashian
LsLLLsL 1011101 93 5L 2s 3|3 Diatonic Dorian
LsLLsLL 1011011 91 5L 2s 2|4 Diatonic Aeolian
LsLLsLs 1011010 90 4L 3s 5|1 Smitonic Vivecan
LsLsLLs 1010110 86 4L 3s 4|2 Smitonic Lorkhanic
LsLsLsL 1010101 85 4L 3s 3|3 Smitonic Sothic
LsLsLss 1010100 84 3L 4s 6|0 Mosh Dril
LsLssLs 1010010 82 3L 4s 5|1 Mosh Gil
LssLsLs 1001010 74 3L 4s 4|2 Mosh Kleeth
LssLsss 1001000 72 2L 5s 6|0 Antidiatonic Antilocrian
LsssLss 1000100 68 2L 5s 5|1 Antidiatonic Antiphrygian
Lssssss 1000000 64 1L 6s 6|0 Anti-archeotonic Antizokalarian
sLLLLLL 0111111 63 6L 1s 0|6 Archeotonic Zokalarian
sLLLsLL 0111011 59 5L 2s 1|5 Diatonic Phrygian
sLLsLLL 0110111 55 5L 2s 0|6 Diatonic Locrian
sLLsLsL 0110101 53 4L 3s 2|4 Smitonic Kagrenacan
sLsLLsL 0101101 45 4L 3s 1|5 Smitonic Almalexian
sLsLsLL 0101011 43 4L 3s 0|6 Smitonic Dagothic
sLsLsLs 0101010 42 3L 4s 3|3 Mosh Bish
sLsLssL 0101001 41 3L 4s 2|4 Mosh Fish
sLssLsL 0100101 37 3L 4s 1|5 Mosh Jwl
sLssLss 0100100 36 2L 5s 4|2 Antidiatonic Anti-aeolian
sLsssLs 0100010 34 2L 5s 3|3 Antidiatonic Antidorian
sLsssss 0100000 32 1L 6s 5|1 Anti-archeotonic Antitamashian
ssLsLsL 0010101 21 3L 4s 0|6 Mosh Led
ssLssLs 0010010 18 2L 5s 2|4 Antidiatonic Antimixolydian
ssLsssL 0010001 17 2L 5s 1|5 Antidiatonic Anti-ionian
ssLssss 0010000 16 1L 6s 4|2 Anti-archeotonic Anti-oukranian
sssLssL 0001001 9 2L 5s 0|6 Antidiatonic Antilydian
sssLsss 0001000 8 1L 6s 3|3 Anti-archeotonic Antihorthathian
ssssLss 0000100 4 1L 6s 2|4 Anti-archeotonic Antilobonian
sssssLs 0000010 2 1L 6s 1|5 Anti-archeotonic Antikarakalian
ssssssL 0000001 1 1L 6s 0|6 Anti-archeotonic Antiryonian
sssssss 0000000 0 0L 7s 0|0 Equiheptatonic Equiheptatonic

Note that since both 0000000 and 1111111 both represent the same scale (equiheptatonic), this entire list is circular, so mathematically, there can't be a "globally" brightest mode. Also, this represents 44 out of 128 possible binary numbers, with the rest being MODMOSses of existing scales. Including all the MODMOSses based on just two step sizes (L and s) produces a diagram such as this by User:Xenoindex.

Including Assigned Values for L and s

So far, the previous table represented scales where the values for L and s are unassigned. However, a large enough edo can contain all six heptatonic MOSses with different step ratios. 26edo, for example, contains 1L 6s, 2L 5s, 3L 4s, 4L 3s, 5L 2s, and 6L 1s with the L:s ratios of 8:3, 8:2, 6:2, 5:2, 4:3, and 4:2 respectively. Equiheptatonic isn't included here because 26 isn't divisible by 7, meaning this list can't be circular (though a very large edo that's divisible by 7 can theoretically include all the heptatonic MOSses and equiheptatonic). Here, instead of a scale code of L's and s's, it's a 7-digit number. The largest value of L across all L:s ratios is 8 and the smallest value of s across L:s ratios is 2. Brightness values are calculated by subtracting 2 from every digit of every scale code and interpreting the resulting number as a base-7 number.

It's important to note that the ordering will vary from edo to edo, since the step ratios will be different, and that these orderings will be different from the ordering of binary encodings.

Scale code Base-7 Decimal MOS UDP MOS name Mode name
8333333 6111111 725502 1L 6s 6|0 Anti-archeotonic Antizokalarian
8228222 6006000 707952 2L 5s 6|0 Antidiatonic Antilocrian
8222822 6000600 706188 2L 5s 5|1 Antidiatonic Antiphrygian
6262622 4040400 480396 3L 4s 6|0 Mosh Dril
6262262 4040040 480228 3L 4s 5|1 Mosh Gil
6226262 4004040 471996 3L 4s 4|2 Mosh Kleeth
5525252 3303030 404418 4L 3s 6|0 Smitonic Nerevarine
5255252 3033030 361200 4L 3s 5|1 Smitonic Vivecan
5252552 3030330 360318 4L 3s 4|2 Smitonic Lorkhanic
5252525 3030303 360300 4L 3s 3|3 Smitonic Sothic
4444442 2222220 274512 6L 1s 6|0 Archeotonic Ryonian
4444424 2222202 274500 6L 1s 5|1 Archeotonic Karakalian
4444244 2222022 274416 6L 1s 4|2 Archeotonic Lobonian
4443443 2221221 274170 5L 2s 6|0 Diatonic Lydian
4442444 2220222 273828 6L 1s 3|3 Archeotonic Horthathian
4434443 2212221 272112 5L 2s 5|1 Diatonic Ionian
4434434 2212212 272106 5L 2s 4|2 Diatonic Mixolydian
4424444 2202222 269712 6L 1s 2|4 Archeotonic Oukranian
4344434 2122212 257700 5L 2s 3|3 Diatonic Dorian
4344344 2122122 257658 5L 2s 2|4 Diatonic Aeolian
4244444 2022222 240900 6L 1s 1|5 Archeotonic Tamashian
3833333 1611111 221292 1L 6s 5|1 Anti-archeotonic Antitamashian
3444344 1222122 156816 5L 2s 1|5 Diatonic Phrygian
3443444 1221222 156522 5L 2s 0|6 Diatonic Locrian
3383333 1161111 149262 1L 6s 4|2 Anti-archeotonic Anti-oukranian
3338333 1116111 138972 1L 6s 3|3 Anti-archeotonic Antihorthathian
3333833 1111611 137502 1L 6s 2|4 Anti-archeotonic Antilobonian
3333383 1111161 137292 1L 6s 1|5 Anti-archeotonic Antikarakalian
3333338 1111116 137262 1L 6s 0|6 Anti-archeotonic Antiryonian
2822822 600600 101136 2L 5s 4|2 Antidiatonic Anti-aeolian
2822282 600060 100884 2L 5s 3|3 Antidiatonic Antidorian
2626262 404040 68628 3L 4s 3|3 Mosh Bish
2626226 404004 68604 3L 4s 2|4 Mosh Fish
2622626 400404 67428 3L 4s 1|5 Mosh Jwl
2552525 330303 57774 4L 3s 2|4 Smitonic Kagrenacan
2525525 303303 51600 4L 3s 1|5 Smitonic Almalexian
2525255 303033 51474 4L 3s 0|6 Smitonic Dagothic
2444444 222222 39216 6L 1s 0|6 Archeotonic Zokalarian
2282282 60060 14448 2L 5s 2|4 Antidiatonic Antimixolydian
2282228 60006 14412 2L 5s 1|5 Antidiatonic Anti-ionian
2262626 40404 9804 3L 4s 0|6 Mosh Led
2228228 6006 2064 2L 5s 0|6 Antidiatonic Antilydian

TAMNAMS-related notes

See User:Ganaram inukshuk/Notes/TAMNAMS.

Mode matrix, interval matrix, and degree matrix

Mode matrix

The notion of an interval matrix is already well-described, but not so much the idea of a mode matrix nor producing an interval matrix from a mode matrix. This is based on the idea of sorting the strings for a mos's modes in lexicographic order to equivalently sort its modes by modal brightness, so pulling from that section, we start with the modes of 5L 2s sorted by modal brightness as an example:

Binary UDP Mode name Scale string
1110110 6|0 Lydian LLLsLLs
1101110 5|1 Ionian LLsLLLs
1101101 4|2 Mixolydian LLsLLsL
1011101 3|3 Dorian LsLLLsL
1011011 2|4 Aeolian LsLLsLL
0111011 1|5 Phrygian sLLLsLL
0110111 0|6 Locrian sLLsLLL

A mode matrix for this is is a 7x7 matrix, consisting of only a single L or a single s in each entry, where each row vector corresponds to one of the mos's modes.

Scale string Mode name Step 1

(c1)

Step 2

(c2)

Step 3

(c3)

Step 4

(c4)

Step 5

(c5)

Step 6

(c6)

Step 7

(c7)

LLLsLLs Lydian L L L s L L s
LLsLLLs Ionian L L s L L L s
LLsLLsL Mixolydian L L s L L s L
LsLLLsL Dorian L s L L L s L
LsLLsLL Aeolian L s L L s L L
sLLLsLL Phrygian s L L L s L L
sLLsLLL Locrian s L L s L L L

Interval matrix

An interval matrix can be defined as the following: for an nxn mode matrix, its column matrix consists of n+1 columns and n rows. For our example, our interval matrix contains 8 columns and 7 rows. Recall that L and s not only stand for characters in a string, but are also in place for actual numbers. Each column vector in the interval matrix represents the sum of consecutive column vectors from the mode matrix; specifically, if the mode matrix's column vectors are enumerated as c1, c2, to cn, then the column vectors of the interval matrix are c1, c1+c2, c1+c2+c3, and so on to c1+c2+c3+...+cn.

An additional column is added before the column of seconds, as these are the roots of the scale. The last column represents an interval produced between the root an the same note one octave above, and all entries in this column are the same size.

For the mode matrix above, the interval matrix can then be calculated as this:

String Mode Unison

(empty substring)

Second

(c1)

Third

(c1+c2)

Fourth

(c1+c2+c3)

Fifth

(c1+...+c4)

Sixth

(c1+...+c5)

Seventh

(c1+...+c6)

Octave

(c1+...+c7)

LLLsLLs Lydian 0 L 2L 3L 3L + s 4L + s 5L + s 5L + 2s
LLsLLLs Ionian 0 L 2L 2L + s 3L + s 4L + s 5L + s 5L + 2s
LLsLLsL Mixolydian 0 L 2L 2L + s 3L + s 4L + s 4L + 2s 5L + 2s
LsLLLsL Dorian 0 L L + s 2L + s 3L + s 4L + s 4L + 2s 5L + 2s
LsLLsLL Aeolian 0 L L + s 2L + s 3L + s 3L + 2s 4L + 2s 5L + 2s
sLLLsLL Phrygian 0 s L + s 2L + s 3L + s 3L + 2s 4L + 2s 5L + 2s
sLLsLLL Locrian 0 s L + s 2L + s 2L + 2s 3L + 2s 3L + 4s 5L + 2s

Degree matrix

Curiously, since the mode matrix consists of only two values, this makes it a logical (or binary) matrix. Likewise, the interval matrix can be converted into a logical interval matrix as such: for each column vector (except for the first and last), the larger of the two values is replaced with 1 and the smaller with 0. The first column vector is all zeros, and the last all ones (though this convention is arbitrary as these two columns are technically not needed). This in turn describes scale degrees as being major or minor, or in the case of the generating intervals, augmented, perfect, or diminished. (The unison and octave are both perfect.)

String Mode d0 d1 d2 d3 c4 c5 c6 c7
LLLsLLs Lydian 0 1 1 1 1 1 1 1
LLsLLLs Ionian 0 1 1 0 1 1 1 1
LLsLLsL Mixolydian 0 1 1 0 1 1 0 1
LsLLLsL Dorian 0 1 0 0 1 1 0 1
LsLLsLL Aeolian 0 1 0 0 1 0 0 1
sLLLsLL Phrygian 0 0 0 0 1 0 0 1
sLLsLLL Locrian 0 0 0 0 0 0 0 1

This also describes a property of the generating intervals: they appear in one specific size in all but one mode; for 5L 2s's perfect 4th, it appears as the smaller size except in the lydian mode where it appears as an augmented 4th, and for the perfect 5th, it appears as the larger size except in the locrian mode where it's a diminished 5th.

Interpreting UDP as two mode enumeration methods

UDP notation is one of many mode notation systems that primarily focuses on how to organize the modes of a mos by modal brightness. This notation necessarily requires the notation to distinguish between the chroma-positive and chroma-negative generators of a mos. One issue with this focus on only its chroma-positive generator is that the generators may "flip". As an example, 5L 2s is said to have a perfect 5th as its generator, but although 2L 3s (the pentatonic scale) is said to have a perfect 4th as its chroma-positive generator, it's common to think of its generator as a perfect 5th regardless.

Modes of 5L 2s
UDP Mode names Scale degrees (starting at C)
1st 2nd 3rd 4th 5th 6th 7th
6|0 Lydian C D E F# G A B
5|1 Ionian C D E F G A B
4|2 Mixolydian C D E F G A Bb
3|3 Dorian C D Eb F G A Bb
2|4 Aeolian C D Eb F G Ab Bb
1|5 Phrygian C Db Eb F G Ab Bb
0|6 Locrian C Db Eb F Gb Ab Bb
Modes of 2L 3s
UDP Mode "names" Scale degrees (independent of 5L 2s) Scale degrees (in relation to 5L 2s)
0d 1d 2d 3d 4d 1st 2nd 3rd 4th 5th 6th 7th
4|0 Pentatonic Phrygian (default mode for sake of example) J K L M N C - Eb F - Ab Bb
3|1 Pentatonic Aeolian (minor pentatonic) J K L M-at N C - Eb F G - Bb
2|2 Pentatonic Dorian J K-at L M-at N C D - F G - Bb
1|3 Pentatonic Mixolydian J K-at L M-at N-at C D - F G A -
0|4 Pentatonic Ionian (major pentatonic) J K-at L-at M-at C D E - G A

Note: the recommended TAMNAMS symbol to denote a downchroma (@) is replaced with the word "at" to prevent the note names from being parsed as email addresses.

This ironically means that major pentatonic is the darkest mode of 2L 3s, though this irony comes from specifying which generator is which.

UDP notation denotes how a scale is produced in terms of how many chroma-positive generators going up (u) and down (d) are needed, notated as "u|d". This can also be interpreted as how many chroma-negative generators are needed going down (d') and up (u'), where the notation is otherwise identical (since d' = u and u' = d). As of writing, TAMNAMS has a proposed mode-naming scheme that drops the number of generators going down, where modes are notated as "u|" instead. An equivalent system that favors a chroma-negative generator can thereby be notated as "|d". In relation to UDP, this is basically the notation of "u|d" separated into two: "u|" and "|d".

In the case of the modes of 2L 3s, even though the perfect 4th is the chroma-positive generator, enumerating modes either using standard UDP notation ("u|d") or the proposed TAMNAMS mode-naming scheme ("u|") and sorting by brightness results in mode 0|4 as being the "last" mode, whereas notating modes as "|d" notates mode 0|4 as the first mode.

This notion of favoring a generator can also extend to mosses that come after a specific mos, such as the chromatic mosses of 5L 7s and 7L 5s for 5L 2s, where the chroma-positive generators (relative to 5L 2s) are the perfect 5th and perfect 4th respectively, though it may be possible to think of the generator of either mos as being the perfect 5th regardless.

Proposal: Equave-agnostic mos names (work-in-progress)

This is an attempt at naming mosses, much like TAMNAMS and with past naming schemes. However, whereas most mos naming systems focus on naming mosses in an octave-equivalent context, this system uses names for an equave-agnostic context, which may be useful when talking about non-octave mosses such as tritave-equivalent or fifth-equivalent scales, or talking about nested mos pattern, such as with a mos cradle.

If anything, this is an exercise in completeness.

Table and scale tree of mos pattern names

2-note mosses (from TAMNAMS)
Mos pair Single-period? Names Prefix Etymology Language
1L 1s Yes trivial triv- Trivial mos, and hence named trivial. Latin
3-note mosses (from TAMNAMS)
Mos pair Single-period? Names Prefix Etymology Language
1L 2s 2L 1s Yes antrial and trial (a)tri- Three-note mosses that descend from the trivial mos. Greek/Latin
4-note mosses (from TAMNAMS)
Mos pair Single-period? Names Prefix Etymology Language
1L 3s 3L 1s Yes antetric and tetric (a)tet- Four-note mosses that descend from antrial. Greek
2L 2s No 2-trivial Two copies of the trivial mos pattern.
5-note mosses (from TAMNAMS)
Mos pair Single-period? Names Prefix Etymology Language
1L 4s 4L 1s Yes pedal and manual ped- and manu- In reference to feet (one big toe and four smaller toes) and hands (four long fingers and one shorter thumb). Latin
2L 3s 3L 2s Yes antipentic and pentic (a)pent- In reference to the pentatonic scale. Note that 2L 3s is pentic, and 3L 2s is anpentic; this is because the pentatonic scale, a subset of the familiar diatonic scale, is of the form 2L 3s. Greek
6-note mosses
Mos pair Single-period? Names Prefix Etymology Language
1L 5s 5L 1s Yes anhexic and hexic (an)hexa- From hex-, meaning six; there is only one pair of single-period hexatonic mosses. Greek
2L 4s 4L 2s No 2-antrial and 2-trial 2 copies of the (an)trial mos patterns.
3L 3s No 3-trivial 3 copies of the trivial mos pattern.
7-note mosses
Mos pair Single-period? Names Prefix Etymology Language
1L 6s 6L 1s Yes ansaptic and saptic (an)sap- These mosses appear further down the mos family tree. Sanskrit is used to differentiate them from the other four mosses. Sanskrit
2L 5s 5L 2s Yes anheptic and heptic (an)hept- In reference to diatonic being a heptatonic scale, perhaps the most well-known heptatonic mos. Greek
3L 4s 4L 3s Yes anseptenic and septenic (an)sept- Latin prefix is used to differentiate these mosses from heptic and anheptic. Septenic has a similar stress pattern as smitonic, coincidentally. Latin
8-note mosses
Mos pair Single-period? Names Prefix Etymology Language
1L 7s 7L 1s Yes anastaic and astaic (an)asta- Follows same pattern with heptatonic mosses where 1L ns and nL 1s are named using Sanskrit. Sanskrit
2L 6s 6L 2s No 2-antetric and 2-tetric 2 copies of the (an)tetric mos patterns.
3L 5s 5L 3s Yes anoctic and octic (an)oct- If going by generational depth from 1L 1s, 3L 5s and 5L 3s are the first octatonic scales encountered. (Greek and Latin prefixes for eight are too similar.) Greek/Latin
4L 4s No 4 copies of the trivial mos pattern.
9-note mosses
Mos pair Single-period? Names Prefix Etymology Language
1L 8s 8L 1s Yes annavic and navic (an)nav- Follows pattern with heptatonic mosses where 1L ns and nL 1s are named using Sanskrit. Sanskrit
2L 7s 7L 2s Yes anennaic and ennaic (an)enna- Follows pattern with heptatonic mosses where the next mos pair after 1L ns and nL 1s are named using Greek. Greek
3L 6s 6L 3s No 3-antrial and 3-trial 3 copies of the (an)trial mos patterns.
4L 5s 5L 4s Yes annovemic and novemic (an)nov- Follows pattern with heptatonic where the 2nd next mos pair after 1L ns and nL 1s are named using Latin. Latin
10-note mosses
Mos pair Single-period? Names Prefix Etymology Language
1L 9s 9L 1s Yes andashic and dashic (an)dash- Follows pattern with heptatonic mosses where 1L ns and nL 1s are named using Sanskrit. Sanskrit
2L 8s 8L 2s No 2-manual and 2-pedal 2 copies of the pedal or manual mos patterns.
3L 7s 7L 3s Yes andekic and dekic (an)dek- Follows pattern with heptatonic mosses where the next mos pair after 1L ns and nL 1s are named using Greek. Greek
4L 6s 6L 4s No 2-pentic and 2-anpentic 2 copies of the (an)pentic mos patterns.
5L 5s No 5-trivial 5 copies of the trivial mos pattern.
Mos Name Mos Name Mos Name Mos Name Mos Name Mos Name Mos Name Mos Name Mos Name
1L 1s trivial 1L 2s antrial 1L 3s antetric 1L 4s pedal 1L 5s anhexic 1L 6s ansaptic 1L 7s anastaic 1L 8s annavic 1L 9s andashic
9L 1s dashic
8L 1s navic
7L 1s astaic
6L 1s saptic
5L 1s hexic
4L 1s manual 5L 4s novemic
4L 5s annovemic
3L 1s tetric 4L 3s septenic
3L 4s anseptenic 7L 3s deckic
3L 7s andeckic
2L 1s trial 3L 2s antipentic 3L 5s anoctic
5L 3s octic
2L 3s pentic 5L 2s heptic
2L 5s anheptic 7L 2s anennaic
2L 7s ennaic

Reasoning for names

Names for these mosses are meant to be as general as possible, following in the spirit of TAMNAMS names for mosses up to 5 notes. In fact, those names are borrowed from TAMNAMS as they already may be used for non-octave periods, and as such, equave-agnostic names are given starting at 6-note mosses, using numerical prefixes that suggest how many steps (or notes) each mos has. Mosses are named in pairs of xL ys and yL xs, where the mos with more small steps than large steps is given the an- prefix, short for anti-.

As there is only one pair of 6-note single-period mosses, 5L 1s and 1L 5s, the pair is named hexic.

With 7-note mosses, there are three pairs of mosses. The problem is to name mosses with a unique name, which is solved by using numeric prefixes based on different languages, not only Greek or Latin. The pair for 5L 2s and 2L 5s is named heptic, in reference to how 5L 2s (TAMNAMS name of diatonic) is the most well-known heptatonic mos, where hepta- is Greek for seven. Similarly, the pair 4L 3s and 3L 4s is the same number of generations away from the root (1L 1s) as 5L 2s and 2L 5s, and is named septenic, where sept- is Latin for seven. The third pair, 6L 1s and 1L 6s, is farther from the root than the other two mosses, and is named saptic, based off of Sanskrit ṣaṭ-, which also means seven.

From here, mosses of n+1 notes follow this pattern: 1L ns and nL 1s are named after Sanskrit, then the following pair is named after Greek, and then Latin. Multi-period mosses are skipped in this process. With 8-note mosses, there are only two pairs, and are named astaic (7L 1s and 1L 7s) and octic (5L 3s and 3L 5s) respectively. As with saptic and heptic, astaic is further from the root than octic. With 9-note mosses, there are three pairs again: navic (8L 1s and 1L 8s), ennaic (7L 2s and 2L 7s), and novemic (4L 5s and 5L 4s). Finally, with 10-note mosses, there are two more pairs: dashic (9L 1s and 1L 9s) and dekic (7L 3s and 3L 7s).

As with TAMNAMS, only mosses with no more than 10 notes are named.

Multi-period mosses are not given their own, unique names. Rather, for a mos xL ys where x and y share a greatest common factor of k, the name reflects some smaller base mos xL ys duplicated k times; for example, 5L 5s is named 5-trivial, and 2L 6s is named 2-antetric.

Proposal for naming equave-agnostic mosdescendants

Mosdescendants are named by adding prefixes to the base names described above, but only to those whose child mosses exceed 10 notes. The proposed prefixes are listed below.

Extension prefix Meaning Reasoning Example
eka- Child mos Sanskrit for one; follows similar logic as eka-elements that Dmitri Mendeleev had named. ekaheptic, referring to 7L 5s and 5L 7s
dvi- Grandchild mos Sanskrit for two; follows similar logic as dvi-elements that Dmitri Mendeleev had named. dviheptic, referring to 5A 12B and 7A 12B
meta- Any mos any number of generations from a named mos The Sanskrit prefix of tri- isn't used to avoid confusion with the tri- prefix used for trial. metaheptic

Mosses related to metallic mosses

Fibonacci numbers and the golden ratio

Let F(n) be a recursive function that returns the nth Fibonacci number.

  • For the base cases of n = 1 or n = 0:
    • If n = 1, then F(1) = 1.
    • If n = 0, then F(0) = 0.
  • For the recursive case of n > 1:
    • If n > 1, then F(n) = F(n-1) + F(n-2)

Mosses whose step ratio approximates the golden ratio will have a step ratio L:s that is F(n):F(n-1), or two consecutive Fibonacci numbers. In relation to a parent mos xL ys, mosses of an arbitrarily large step ratio F(n):F(n-1) (where n is arbitrarily large) will contain a sequence of mosses of the form (F(k)x+F(k-1)y)L (F(k-1)x+F(k-2)y)s, where F(k), F(k-1), and F(k-2) are the kth, (k-1)th, and (k-2)th Fibonacci numbers. Due to mos recursion, the mos F(n)x+F(n-1)y)L (F(n-1)x+F(n-2)y)s contains xL ys, as well as every mos between xL ys and F(n)x+F(n-1)y)L (F(n-1)x+F(n-2)y)s. As an example, golden meantone describes the mos 5L 2s whose step ratio approaches the golden ratio. This also describes a series of mos descendants that contain 5L 2s as a subset, which are 7L 5s, 12L 7s, 19L 12s, 31L 19s, 50L 31s, and so on. This is to say that the aforementioned mosses are supported by golden meantone.

Any arbitrary mos is the start of a golden mos sequence (the temperament-agnostic equivalent of a golden temperament), even if it coincides with that of another mos.