Music Theory Trivia

Chord buttons don't need to stay where they are. Check out some other ideas. What notes are in a chord. Nonstandard chords.

Music Theory Trivia

Postby Bob Lewis » Tue Jun 09, 2009 7:46 am

In reviewing sources re chords, I made some notes that might be of interest to some. I expanded on the subject in some cases.

1) The practice of using Roman numerals as chord names associated with scale steps; while not specific as to key, a generic chord name; is attributed to Weber, writing in German in 1820. Our V7, for example, dates back to 1820, which is relatively recent in musical history, approximately at the beginning of the Romantic period of classical music, drawing on analysis of works by composers such as Bach, Beethoven, Handel, Mozart, Haydn and other icon composers, more in the period just preceding the work of Brahms and a few years before the death of Beethoven.

While Roman numerals are used in text to distinguish from Arabic numbers used for extensions of triads like V7 and I9 et al., speech sounds like two numbers, such as "five seven".

2) The Alphabet scale is attributed to Guido d'Arezzo, an Italian monk living near 1000 AD, documented in his Micrologus. The series ABCDEFG is [A minor] and is derived from a hymn written (by Guido) especially to have a melody that moves progressively up a scale. It was a device for training church choristers. Six of the letters ABCDEFG are actually a translation of the first letter of each word in the hymn that occurs at each scale step. Those same words are the basis of solfeggio, the discipline for sight singing, relying on learning the sound of intervals. The familiar do-re-mi-fa-sol-la-ti diatonic scale came from the same words, although "do" was originally "ut".

There are other elements of music theory that trace to Guido d'Arezzo's work. It was all an evolutionary process, building on existing convention, with Guido d'Arezzo's actual documentation, the Micrologus, serving as the seminal work.

3) The first use of the terms tonic, dominant, and subdominant to designate the root of a scale and its two fifth intervals is attributed to Rameau, writing in French in 1760. These terms were eventually incorporated in a practice to assign a name to each step in a scale. The terms are used very little colloquially or even academically, the scale most often expressed as numbers in speech and Roman numerals in text. These would be the easier ways to remember the sequential or relative order of the scale degrees. The terms are then mainly pedantic. I believe then that altering the term "dominant" to indicate a type of 7th chord, an entire class rather than one specific to a key, does relatively little harm, creates little confusion. If one speaks in terms of key context, V7 ("five seven") would be the better communication than "dominant 7", since there would then be 12 dominant 7ths from which to choose. In the context of a key then, it would be important to avoid the term "dominant 7" without including a letter name, the complete name of a discrete chord. "V7" would really mean something, while "dominant 7" would be incomplete information. That would be because the real significance of the word "dominant" had been discarded, when using [dominant] to refer to an entire class of chords with the same interval structure.

4) The order of scale degree names comes from inverting their origin positions to occur all within a single scale. The subdominant, submediant, and leading tone in concept occur below the tonic, and thus their respective names. The conventional order of Tonic, Supertonic, Mediant, Subdominant, Dominant, Submediant, Leading Tone is more correctly Subdominant, Submediant, Leading Tone, Tonic, Supertonic, Mediant, Dominant.

Subdominant is a perfect fifth below the Tonic, and Dominant is a perfect fifth above. Empirically then, we can interpolate that the term Dominant designates "above the Tonic" or "the higher of two dominants (perfect fifths), as compared to subdominant". The term Subdominant, rather than designating "below the Dominant", designates "below the Tonic" or "the lower of two dominants (perfect fifths)". The term [Dominant] means only relative position, not its importance in the scheme. The dominant and subdominant are peers in their natural positions in that both are a perfect fifth emanating from the tonic but in different directions, ascending and descending, respectively. Following inversion to the common octave, the subdominant becomes a fourth above the tonic, appearing to be entirely different in character than the dominant interval.

Note that the Tonic is the base tone or root of a scale, whether Major according to a key signature or minor according to modal interpretation of a major key signature. Thus the Tonic designation can be reassigned when a piece modulates from Major to minor. That also then means the intervals between scale degree names are variable. A Major Tonic/Mediant third interval is different than a minor Tonic/Mediant third interval.

5) An example of variation in references to chords is the II7 (two seven), aka "V of V" or "secondary dominant". An actual example would be a piece in G calling for an A7 in addition to the expected V7 of D7. The very same chord in the same key signature is designated the IV7, if in relative minor mode. In Em, for example, key signature of G (Major), A7 occurs or can be viewed as built on the fourth (4th) step of the Em scale.

I favor the practice of simplifying with use of mostly Roman numerals, always anchored in the Major scale of the key signature regardless. That better acknowledges the existence of modes, starting scales on steps other than the key root. I believe it is confusing to move the tonic for minor, when key signatures are expressed as Major, so upper and lower case Roman numerals serve well to designate fixed names of chords built on steps of a Major scale, not minor. This means a relative minor (chord) would not become a lower case I (i). It would remain a vi, a lower case Roman numeral (6), its name within a Major scale, the name of the key signature. Harmonic minor would be vi-ii-III7, not i-iv-V7.

I also favor actively avoiding the term [dominant] as now little more than colloquial, passing as pseudo intellectual. It adds little if any information, and one can substitute a less confusing term and avoid the ambiguity.

When I have a cluster of chord bar buttons with the underlying chords, and name them and base the fingering logic on the functions of the chords in Major keys, this is how they look, and I don't suddenly have aliases for them, when I happen to be playing in a minor key:

------I7----V7---II7----VI7--III7
--IV----I-----V
----ii---vi----iii

Stated as an example key of C, the above would look like this:

X-----C7----G7----D7---A7---E7
--F-----C-----G
---Dm----Am----Em

The pattern would be the same in some other key, while transposed to different letter names.

I hope it is obvious that this is just a subset of a larger scheme to serve more than one key. The 7ths on the right end of a real chord set may actually step down into lower button rows.

The string of 7th chords on the right and one on the left would be native to other keys but serve to bring in the notes not native to C. The CDEFGA in the majors and minors take on Bb, F#, C#, G#, D#, and B, using the 7ths shown, making a complete 12 tone scale.

There are a number of other approaches to exactly how these layouts are patterned, but this serves as an example that means something to me, while being close to common convention.
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