#1
I've yet to find any explanation for how the pitches (or intervals) are named for octatonic scales, as by definition these involve enharmonic choices.

Anyone know the logic for determing which pitch letter gets duplicated?

A few ways the half-whole scale could be spelled is

1, b2, #2, 3, #4, 5, 6, b7

1, b2, b3, 3, #4, 5, 6, b7

1, b2, b3, 3, b5, 5, 6, b7
#2
If it is 8 notes, just make it 1-8. So for half-whole and whole-half:

1 b2 3 b4 5 b6 7 b8
1 2 b3 4 b5 6 b7 8
There's no such thing; there never was. Where I am going you cannot follow me now.
#3
I'd call "the most valid" spelling one that doesn't have a sharp and flat on adjacent notes and is made up of only major and minor seconds (no diminished thirds). So I see a couple options.

1 b2 b3 3 #4 5 6 b7

1 #1 #2 3 #4 5 6 b7


For whole half it wouldn't really make much difference, there'd still be two options.

1 2 b3 4 b5 b6 6 7

1 2 b3 4 #4 #5 6 7


There could be other possibilities that I'm not seeing but I think it's just those two. But really it doesn't matter that much. There's no set way to notate it.
#4
I'd prefer the first one. Isn't C HW usually used over a C7 chord? So in that way it would make most sense. It shows all the extensions. Having two thirds or two fifths is kind of weird. But it of course depends on your approach. If we are talking about CST, the first one makes most sense.
Quote by AlanHB
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Last edited by MaggaraMarine at Jan 24, 2016,
#5
I agree that context would determine it for me - ie chord tones first, so for a HW (assuming a dom7 chord) I'd use b2 and #2.
1 b2 #2 3 #4 5 6 b7

For WH on a dim7, I'd probably use bb7 and maj7:
1 2 b3 4 b5 b6 bb7 7

That also aligns with the HW as modes of the same scale used in the same way: as V7b9 or viio7, seeing as the viio7 chord is rooted on the 3rd of the 7b9.

... but then dim7s get used in all kinds of places, and the broader context might dictate the best enharmonics.
Last edited by jongtr at Jan 24, 2016,
#6
Good answers here. The most correct answer is an interesting combination of everything here.

You do need to double one letter, so we tend to spell JRF's way for an octatonic scale in classical and concert music.

However, when we cross over into jazz land, where everything is chord based, Maggara is more correct: We want to bring the chords out.

So for C7: C Db Eb E F# G A Bb (we tend to spell #9 as b3 due to voice leading conventions)

or for Cdim7: C D Eb F Gb G# A B (note the 4 dim7 chord tones with leading tones underneath).

^EDIT: That C WH spelling is a mistake. See below.
"There are two styles of music. Good music and bad music." -Duke Ellington

"If you really think about it, the guitar is a pointless instrument." - Robert Fripp
#7
I'm not sure there's a formally correct way to label 8 tone scales. Usually I'd go with whatever solfege makes most sense, or what makes most sense in context (that is, chord tones). I supposed you'd just pick which scale degree you're okay with having twice. Most of the time I think the redundancy gets put on scale degree 2, since it's fairly common to have play both b9 and #9 over a dominant chord (aka altered dominant).

It's all about context. How you spell things on the staff is not always the same as when you go back to analyze.
#8
Quote by Jet Penguin

So for C7: C Db Eb E F# G A Bb (we tend to spell #9 as b3 due to voice leading conventions)
So you'd use a C7b10 chord symbol, if the Eb was included?
Quote by Jet Penguin

or for Cdim7: C D Eb F Gb G# A B (note the 4 dim7 chord tones with leading tones underneath).
Despite the fact that - strictly speaking - the A should be Bbb (diminished 7th)?
Or does that depend on the function of the chord?
(Just checking )
#10
Jon:

Nope, I'd use the symbol C7#9, but I'd spell the note Eb on the staff. It's just a weird exception that happens as often as D#.

We often spell it on jazz charts as a b10 because it usually resolves down, and we try to preserve the motion of accidentals.

D# resolving to C looks weird; Eb to C, not so much.

The A SHOULD be a Bbb, that was just a classic case of me being stupid.

C WH (for real): C D Eb F Gb Ab Bbb B

^This is the right spelling on paper, because we have the dim7 chord tones (1, b3, b5, d7) and the extensions (9, 11, b13, maj7) all spelled correctly as far as CST goes.

However, I won't blame anyone who shifts around the enharmonics to make it look nicer. We could just as easily do C WH like this:

C D Eb F F# G# A B

But that tells us less about the harmony involved, assuming that harmony is a dim7 chord.

Bottom line, try to spell in a way that tells us about the harmonic progression.
"There are two styles of music. Good music and bad music." -Duke Ellington

"If you really think about it, the guitar is a pointless instrument." - Robert Fripp
#11
Quote by Jet Penguin

However, I won't blame anyone who shifts around the enharmonics to make it look nicer. We could just as easily do C WH like this:

C D Eb F F# G# A B


I took a jazz class in college with a very highly regarded professor, and he also said to spell the bb7 enharmonically whenever it's easier to read. On jazz charts the harmony is indicated, so there's no loss of information. A mis-spelled bb7 on a score, however, might leave the players unclear as to the harmony.
Last edited by cdgraves at Jan 25, 2016,
#12
Exactly.

Whether it be chord implications or just ease of reading, you want to spell as informatively as possible.
"There are two styles of music. Good music and bad music." -Duke Ellington

"If you really think about it, the guitar is a pointless instrument." - Robert Fripp
#13
Quote by cdgraves
I took a jazz class in college with a very highly regarded professor, and he also said to spell the bb7 enharmonically whenever it's easier to read. On jazz charts the harmony is indicated, so there's no loss of information. A mis-spelled bb7 on a score, however, might leave the players unclear as to the harmony.
Right.
So you'd often see the chord C-Eb-F#-A indicated as "Cdim7", whereas those notes - strictly speaking - spell F#dim7. If it's resolving to G or Gm, then it IS F#dim7, functionally speaking.
But if a C bass is wanted - which is the likely implication of "Cdim7" to a jazz player - it's too fussy to write "F#dim7/C", just to please some anal theorist... . (Actually, if resolving to G or Gm, a bassist might well put a D under it anyway...)
Jazz enjoys the fact that dim7s are functionally ambiguous, so the enharmonics are generally neither here nor there - except to make best sense with the surrounding context (ie the most readable option).
Last edited by jongtr at Jan 26, 2016,
#14
Yes. In my admittedly limited experience, they're pretty much always leading tone dim7 chords. I haven't seen much movement by 5th from dim7 chords. m7b5 moves by 5th, but not dim7.

Anal theorist note: Cdim7 has a Gb, not F#! The symmetry of the dim7 means that any spelling alteration creates a mis-spelling for the inverted roots, as well.
Last edited by cdgraves at Jan 26, 2016,
#15
Quote by cdgraves
Yes. In my admittedly limited experience, they're pretty much always leading tone dim7 chords. I haven't seen much movement by 5th from dim7 chords. m7b5 moves by 5th, but not dim7.
Dim7s can move three (and only three!) ways:

1. one note (any note) of the dim7 rises a half-step to the root of the following chord;
2. one note (any note) of the dim7 descends a half-step to the root of the following chord;
3. one note (any note) of the dim7 is the same as the root of the following chord.

#1 is the commonest, derived from the dim7's origins as vii of the minor key (7th degree of harmonic minor). It's used in major keys that way too, and also as a secondary viio7.

#2 is the rarest, and AFAIK has no conventional name. Often it's working like function #1 but in reverse - ie, the chord before the dim7 is like the tonic of which the dim7 is its vii; the dim7 then goes on down to the next chord. Chromatic voice-leading is involved naturally.
You get this kind of change in a few Jobim tunes, and in Night and Day.

#3 is the "common tone diminished", usually preceding, or acting as an embellishment of, a major chord (doesn't work so well with minors).
Quote by cdgraves

Anal theorist note: Cdim7 has a Gb, not F#!
Strictly speaking, yes. And Bbb, not A.
Quote by cdgraves

The symmetry of the dim7 means that any spelling alteration creates a mis-spelling for the inverted roots, as well.
Yes, but - if I understand you right - only if you regard a bass note as a "root".

Dim7s used as vii chords are quite easy to spell correctly (relative to the local harmonic minor scale), and inversion doesn't mean they need re-spelling - nor re-naming, IMO, although it's often clearer (for a reader, especially a bass player) to name an inverted dim7 after its bass note.

Eg, as I said, if "Cdim7" is resolving to G or Gm, then really it's an inversion of F#dim7. C Eb F# A is then the correct spelling - it's calling it "Cdim7" that is (strictly speaking) incorrect.
But if we want a bass player with a chord chart to play C, then calling it Cdim7 is probably best.

If the same chord (same voicing) is resolving to E or Em, then really it's an inversion of D#dim7, and should be spelled C-D#-F#-A.
Etc...
Adim7 = A C Eb Gb (in any inversion), and resolves to Bb or Bbm
Cdim7 = C Eb Gb Bbb (in any inversion), and resolves to Db major - or C#m, in which case we should call it B#dim7 - B#-D#-F#-A!


Used as a common tone diminished, OTOH, "Cdim7" should (probably?) be spelled C-D#-F#-A, because D# and F# will lead up to E and G.

With the third kind, the descending chromatic diminished, spelling ought (again) to relate to the voice-leading and the tonal context.
Last edited by jongtr at Jan 27, 2016,
#16
Octatonic scales are part of a group called "symmetrical scales," and yes, they present problems. Set theory is the best way to describe them IMO
#18
C Dim 7 - I just follow the chord formula: minor triad (b5) bb7 - C Eb Gb Bbb.

However this is for correctness sake and correctly acknowledging the intervals.

But for communications sake, and maintaining clarity where being "correct" on the notes is not the priority or objective, then I'd say "Play C Eb Gb and A". Because I'm communicating musical direction, and not musical concept.

I generally do not mess with Octa-tonics however. Most likely I'd choose the approach that makes things clear. If there is a defined scale formula 1, b2, 2 etc, then I'd just use that as the basis for my naming of the notes.

Best,

Sean
#19
Quote by jongtr
Dim7s can move three (and only three!) ways:

1. one note (any note) of the dim7 rises a half-step to the root of the following chord;
2. one note (any note) of the dim7 descends a half-step to the root of the following chord;
3. one note (any note) of the dim7 is the same as the root of the following chord.

#1 is the commonest, derived from the dim7's origins as vii of the minor key (7th degree of harmonic minor). It's used in major keys that way too, and also as a secondary viio7.

#2 is the rarest, and AFAIK has no conventional name. Often it's working like function #1 but in reverse - ie, the chord before the dim7 is like the tonic of which the dim7 is its vii; the dim7 then goes on down to the next chord. Chromatic voice-leading is involved naturally.
You get this kind of change in a few Jobim tunes, and in Night and Day.

#3 is the "common tone diminished", usually preceding, or acting as an embellishment of, a major chord (doesn't work so well with minors).
Strictly speaking, yes. And Bbb, not A.
Yes, but - if I understand you right - only if you regard a bass note as a "root".

Dim7s used as vii chords are quite easy to spell correctly (relative to the local harmonic minor scale), and inversion doesn't mean they need re-spelling - nor re-naming, IMO, although it's often clearer (for a reader, especially a bass player) to name an inverted dim7 after its bass note.

Eg, as I said, if "Cdim7" is resolving to G or Gm, then really it's an inversion of F#dim7. C Eb F# A is then the correct spelling - it's calling it "Cdim7" that is (strictly speaking) incorrect.
But if we want a bass player with a chord chart to play C, then calling it Cdim7 is probably best.

If the same chord (same voicing) is resolving to E or Em, then really it's an inversion of D#dim7, and should be spelled C-D#-F#-A.
Etc...
Adim7 = A C Eb Gb (in any inversion), and resolves to Bb or Bbm
Cdim7 = C Eb Gb Bbb (in any inversion), and resolves to Db major - or C#m, in which case we should call it B#dim7 - B#-D#-F#-A!


Used as a common tone diminished, OTOH, "Cdim7" should (probably?) be spelled C-D#-F#-A, because D# and F# will lead up to E and G.

With the third kind, the descending chromatic diminished, spelling ought (again) to relate to the voice-leading and the tonal context.

Yes, exactly. When you see "Cdim7" used in context, it doesn't really necessarily function as Cdim7. It is just named after its bass note. I mean, writing Cdim7-C is a lot easier to read than D#dim7/C-C, even though the latter one is technically more correct.

In a similar way a tritone substitution for, let's say G7, shouldn't really be called Db7 (for voice leading reasons). The chord tones in that chord are not Db, F, Ab and Cb. They are Db, F, Ab and B. That's because the "7th" of the chord functions as the leading tone. It definitely functions as a B, not as a Cb. But that's the simplest way of writing the chord and everybody understands what it means. It's not "technically correct" but it is simple. And nobody cares about being 100% "technically correct" when they are playing music.

Sometimes you need to make compromises to make it as easy to read as possible. Nobody would write the #9 in E7#9 chord as Fx. Well, that depends on the context of course, but if it functions as the dominant for Am, it's really not an Fx, it's a G (which is usually used in a descending line like G-F-E - writing that as Fx-F-E would be awkward and not even correct). But what would be a good chord symbol for that? E7#9 is good enough.

Fx would be used if the melody went like E|-3-4-3-4-3-4 (over an E7#9 chord). Then the #9 would actually function as an Fx and the correct way to notate that would be Fx-G#-Fx-G#-Fx-G#.
Quote by AlanHB
Just remember that there are no boring scales, just boring players.

Gear

Bach Stradivarius 37G
Charvel So Cal
Fender Dimension Bass
Hartke HyDrive 210c
Ibanez BL70
Laney VC30
Tokai TB48
Yamaha FG720S-12
Yamaha P115
Last edited by MaggaraMarine at Feb 8, 2016,
#20
^Yup.

Or in other words, writing music and reading music are two different things. If something looks easier...it will be played as if it WAS easier...regardless of what makes sense from an analysis perspective

I mean, technically, you could have a 7 line staff and give every pitch its own line or space. F# and Gb are one line, while G and F are the spaces above and below respectively. You no longer need to use enharmonics in your writing, and octatonics as well as other non traditional harmony looks clean as hell! Also, its perfect for 24TET because you can use sharps and flats to notate quarter tones very cleanly and consistently. However, its cumbersome as fuck to read because the vertical space just looks so large.
Last edited by bassalloverthe at Feb 10, 2016,