Talk:Rule of the octave

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Interwiki

If the French and German wikis had articles on this subject they would presumably be at fr:trait d'octave and de:octave-gang according to Hiles, John (1882). A catechism of harmony, thorough-bass, and modulation, with examples, p.82. ISBN 1141609991. Hyacinth (talk) 02:42, 15 April 2011 (UTC)[reply]

Hiles is wrong here, at least as of today: In German, this is called de:Oktavregel. --User:Haraldmmueller 10:36, 12 September 2018 (UTC)[reply]

Errors in Graphic

The visual example currently on the page has mistakes which might be a little confusing or else misleading.

In the first line (ascending scale), the fourth chord should be labelled a ii 6/5, not IV 6/5. It would be IV if the F was in the bass without a D present. Perhaps I am mistaken, but the presence of the D makes this a Dm7/F, or a ii 6/5. Also, the sixth chord is labelled IV 6/5, except that there is no 5 present (an E), meaning it should only read IV 6. The penultimate chord has no figures, but is quite obviously a V 6/5 and should have those figures to indicate such.

The descending line also has an error. The third chord (over A, scale degree six, submediant) has figures for V/V 6/4, except that the seventh (3) is present, meaning the figures should read 4/3 or 6/4/3.

Is this example taken directly from the sources or just compiled by an amateur? The citations would seem to imply that the example comes from both sources, but unless I am missing some pedagogical element, I doubt that both sources would show exactly the same mistake. Looking at the Hiles source here (https://archive.org/details/acatechismharmo00hilegoog), page 82 demonstrates the rule of the octave for a major scale ascending and descending. Page 82 should be cited if it is indeed the source. If it is the source, we can see the error created - perhaps by the grahpic creator - in moving the penultimate and antepenultimate figures ahead by one tone and misharmonising or mislabelling the remaining errors. Zeppelin42 (talk) 06:33, 17 September 2014 (UTC)[reply]

I've just replaced the faulty graphic with an in-line score. However, according to Hiles, the third chord on the descending bass line should be A_#6 instead of A_#6_4_3. Unfortunately I was not able to harmonise A_#6 without adding a parallel octave. --SelfishSeahorse (talk) 21:30, 6 September 2015 (UTC)[reply]

What about

$\new PianoStaff << \new Staff { \new Voice = "right" { \relative c' { \clef treble \time 4/4 <e g c>4 <f g b> <e g c> <d a' c> | <d g b> <c f c'> <f g d'> <e g c> \bar "||" | <g c e> <d g d'> <c fis a> <d g b> | <d g b> <c g' c> <f g b> <e g c> \bar "|." | } } } \new Staff { \new Voice = "left" { \relative c { \clef "bass" c4 d e f | g a b c | c b a g | f e d c | } } } \new FiguredBass { \figuremode { <_>4 <4 3> <6> <6 5> | <_> <6> <6 5> <_> | <_> <6> <6+> <_> | <2> <6> <4 3> <_> | } } >>$

or

$\new PianoStaff << \new Staff { \new Voice = "right" { \relative c' { \clef treble \time 4/4 <e g c>4 <f g b> <e g c> <d a' c> | <d g b> <c f c'> <f g d'> <e g c> \bar "||" | <g c e> <g g d'> <c, fis c'> <d g b> | <d g b> <c g' c> <f g b> <e g c> \bar "|." | } } } \new Staff { \new Voice = "left" { \relative c { \clef "bass" c4 d e f | g a b c | c b a g | f e d c | } } } \new FiguredBass { \figuremode { <_>4 <4 3> <6> <6 5> | <_> <6> <6 5> <_> | <_> <6> <6+> <_> | <2> <6> <4 3> <_> | } } \new Lyrics { \lyricsto "left" { I V I II | V IV V I | I V V/V V | V I V I | } } >>$

--User:Haraldmmueller 09:41, 12 September 2018 (UTC)[reply]

The example does not reproduce the one given by John Hiles, which consists merely in the bass ascending and descending lines, with Arabic numerals above; there is no fundamental bass in Roman numerals, nor the chords represented here, and the Arabic numerals are different. This example should be removed, and replaced by another one. — Hucbald.SaintAmand (talk) 12:44, 26 January 2021 (UTC)[reply]

Parallel fifths in example?

The "parallel fifths" identified by @Pbarreto.crypto are an example of "piano fifths"; a voice assignment for SATB can easily avoid them like this:

A and T cross each other on the 7th chord. As T is a male voice and A a female one, there will be no perception of parallel fifths for the listener. Thus, it is not at all clear that the given example contains an "error". User:Haraldmmueller 07:04, 31 January 2024 (UTC)[reply]