A Chord in Time: The Evolution of the Augmented Sixth from Monteverdi to Mahler

Mark Ellis

• Publisher: Routledge
• Year: 2017
• Print ISBN:
  9780754663850
• eBook ISBN:
  9781351578134
• Topic: Media & Performing Arts
• Subtopic: Music

For centuries, the augmented sixth sonority has fascinated composers and intrigued music analysts. Here, Dr Mark Ellis presents a series of musical examples illustrating the 'evolution' of the augmented sixth and the changing contexts in which it can be found. Surprisingly, the sonority emerged from one of the last remnants of modal counterpoint to survive into the tonal era: the Phrygian Cadence. In the Baroque period, the 'terrible dissonance' was nearly always associated with negative textual imagery. Charpentier described the augmented sixth as 'poignantly expressive'. J. S. Bach considered an occurrence of the chord in one of his forebear's motets 'remarkably bold'. During Bach's composing lifetime, the augmented sixth evolved from a relatively rare chromaticism to an almost commonplace element within the tonal spectrum; the chord reflects particular chronological and stylistic strata in his music. Theorists began cautiously to accept the chord, but its inversional possibilities proved particularly contentious, as commentaries by writers as diverse as Muffat, Marpurg and Rousseau reveal. During the eighteenth century, the augmented sixth became increasingly significant in instrumental repertoires - it was perhaps Vivaldi who first liberated the chord from its negative textual associations. By the later eighteenth century, the chord began to function almost as a 'signpost' to indicate important structural boundaries within sonata form. The chord did not, however, entirely lose its darker undertone: it signifies, for example, the theme of revenge in Mozart's Don Giovanni. Romantic composers uncovered far-reaching tonal ambiguities inherent in the augmented sixth. Chopin's Nocturnes often seem beguilingly simple, but the surface tranquillity masks the composer's strikingly original harmonic experiments. Wagner's much-analyzed 'Tristan Chord' resolves (according to some theorists) on an augmented sixth. In Tristan und Isolde, the chord's mercurial

Chapter 1
Key Concepts

The aim of this chapter is to introduce, for the non-specialist reader, some of the basic concepts underlying the ‘evolution of the augmented sixth sonority’. I have used the term ‘sonority’ rather than ‘chord’ here because the augmented sixth may not always have been conceived as a ‘chord’ in the commonly accepted sense (that is, as a verticality, as part of a triad or as part of an extended chord formation). At least some instances of the augmented sixth – and probably most of the examples from before 1700 – can be interpreted as the ‘by-products’ of simultaneous but independent melodic lines. However, to begin with, I shall introduce these basic elements in the mythical style familiar from harmony pedagogy: the four-part chord progression. The concepts to be discussed here include the group of chords collectively known as augmented sixths, two chordal progressions (the Phrygian cadence and the circle of fifths) and two other distinctive chromatic chords (the Neapolitan sixth and the subdominant minor seventh).

The origin of these distinctive stylistic features can be detected in the rapidly changing musical worlds of the late Renaissance and early Baroque periods. They apparently crystallized at a time of fine balance between modality and early tonality, an unstable state that could be thought of as ‘proto-tonality’. Intriguingly, the specific chromatic elements discussed below are curiously related to one particular mode, the Phrygian, which will, after reviewing the augmented sixth as a ‘text-book’ entity, be the starting point for the historical survey. Various augmented sixths (and some related chords) are shown in Example 1.1. For present purposes, these are shown in what may be considered a C major context.

Example 1.1 Various augmented sixths and related chords

Traditionally, three subspecies of augmented sixth are identified: Italian, French and German (It6, Fr6 and Ger6). These geographical names appear to have originated in the early nineteenth century and reflect only the vaguest of actual national usage. John Calcott’s Grammar of Music – a widely read and extensively reprinted pocket reference book – identifies by name these national variants of what the author describes as the ‘extreme sharp sixth’ in the first edition, published in london in 1806.¹ Possibly Calcott’s preference for the ‘elegance of the Italian’ and ‘strength of the German’ compared with the ‘feebleness of the French’ was coloured by over-riding political concerns of the day. The sources of information on the ‘extreme sharp sixth’ are cited as Rousseau and Framery.² Interestingly, these are both French theorists of the later eighteenth century, though neither writer specifically identifies the chords by nationality. From an analytical perspective, the geographical classifications are not particularly illuminating, since any meaningful distinction can easily be blurred by the addition of non-harmony notes or inessential notes, such as passing notes or appoggiaturas.

Visually and aurally, the most arresting feature of the augmented sixth is its simultaneous ‘flatness and sharpness’, a combination that exerts a natural outward thrust because of the tendency for sharp notes to resolve up and flat ones down. The Janus-like flat and sharp qualities generally presuppose a broader chromatic context, which will be explored later in more detail. This duality also poses an interesting challenge concerning the preparation for the augmented sixth chord, which is generally more likely to be found in minor than in major contexts. However, this is not always the case, as Example 1.2 illustrates.

Example 1.2 Haydn, Symphony No. 19 (1759)

Except for the German sixth (shown by the asterisk), the exposition (the opening 45 bars) of the first movement of Haydn’s symphony remains resolutely diatonic, initially in D major and subsequently in A major (there is also a chromatic passing note in bar 13 and a chromatic appoggiatura in bar 34).³ The augmented sixth interrupts the galant sensibility of the proceedings; its abruptness is emphasized by the sudden forte dynamic, and its angularity by the false relation C♯–C♮ in the first violins. Clearly Haydn intended this dramatic dissonance to startle his aristocratic audience. In general, however, when the chord appears within a minor key, the ‘flat component’ can be prepared more smoothly. Indeed, the augmented sixth often ‘emerges’ from a chord on the flattened sixth. The chord progression VI–Ger6 in the minor key, or ♭VI–Ger6 in the major, became a cliché in the early Classical period. More rarely, the composer approaches the chord from the ‘sharp side’ – usually as a diminished seventh – which often requires particularly careful handling (Example 1.3).

Example 1.3 Mendelssohn, Song Without Words Op. 102/6

In many cases, the interval of the augmented sixth, Example 1.1(a), would resolve outward to an octave, Example 1.1(b). In a ‘typical example’ from the early Classical period, say around 1780, this octave (b) would outline the dominant of the key being approached. The octave might be completed as either chord V itself (Ex. 1.1(i)) or as a cadential six-four chord (I 6/4) which will in turn, of course, resolve to chord V. Whether the upcoming key area is major or minor, the approach is very likely to be through the minor; it is a distinctive Classical trait to approach, say, the dominant major via the dominant minor.

This type of context (Ex. 1.1 (h) to (i)) appears to establish the augmented sixth as an ‘approach’ chord to the dominant. Indeed, it is quite easy to interpret the French sixth as a type of supertonic chord. In C major, for example, the supertonic seventh comprises the notes D–F–A–C (Ex. 1.1 (f)). There are two common chromatic variants of the supertonic seventh: the ‘secondary dominant’, D–F♯–A–C, and the version ‘borrowed from the tonic minor’, D–F–A♭–C. The French sixth can be viewed as a type of conflation of these two chromatic variants: D–F♯–A♭–C (Ex. 1.1 (g)). Of course, the commonly encountered inversions of the supertonic triad and French sixth differ: the supertonic is usually voiced in first inversion (in this context the ‘chord of the sixth’ refers to the figured-bass shorthand for first inversion) while the French sixth is, from its earliest occurrences, generally found in second inversion (the sixth here refers to the most characteristic interval of the chord, the augmented sixth itself).

From an analytical viewpoint, identifying the exact inversion of the chord is less significant than observing whether the sharp or flat note is set in the lowest voice, because this bass note defines the two substantive alternatives for this chord. However, from a historical perspective, the inversions assume great significance. The apparently problematic nature of the inversions of the augmented sixth was a major concern for theorists from the second quarter of the eighteenth century (when the chord was first extensively discussed) onward. In fact, the ‘problem’ arose precisely because theories of chords and inversions were being formulated. The augmented sixth could not easily be accommodated within these conceptual frameworks because some inversions (for example, Ex. 1.1 (g)) incorporate a diminished third (F♯–A♭ in this instance). Many commentators rejected this interval as unusable⁴ – indeed, its usability was still being denied by some influential commentators well into the nineteenth century.⁵ That the augmented sixth was discussed – or, at least, specifically identified – by theorists of the eighteenth century was initially due to this particular quality. Other chromatic chords, such as the Neapolitan sixth, were discussed less (if identified at all) because their interval construction was not, in abstract, exceptional.⁶ Nevertheless, it remains that the voicing most usually encountered has the flat note in the bass, and the ‘sharp inversion’ is correspondingly rare.⁷

The German sixth, which is the most frequently encountered version of the chord, presents a special case. From a purely technical standpoint, it contains a perfect fifth; this poses an interesting challenge if it is to be resolved directly to the dominant. In these circumstances, Mozart and Beethoven seem, on frequent occasions, to have been willing to countenance the resulting consecutive fifths (Ex. 1.4 shows the string parts from bar 167 of the first movement of Mozart’s Symphony in E♭ major K. 543, with striking parallel fifths between second violins and violas). Perhaps the very strong upward drive of the sharp note ‘permitted’ this irregularity by counteracting the downward slide of the parallel fifths. Schoenberg even refers to this type of resolution as ‘Mozart fifths’.⁸ In a major key, the alternative resolution on a cadential 6-4 usually involves a rather rich chromaticism. In this type of context, the ‘fifth’ above the bass of the German sixth is often notated as a sharp rather than a flat; compare 1.1(j) with the more conventionally notated 1.1(e). An early example can be found in the finale of Schubert’s Symphony No. 9 in C major, The Great, b. 693.

Example 1.4 Mozart, Symphony K. 453

More significantly, the German sixth sounds, in abstract, like a dominant seventh (Example 1.5 (a) and (b)); the dominant seventh is, of course, a far more common chord than an augmented sixth. From the early eighteenth century, composers began exploring this ambiguity through enharmonic resolution: the chord would be approached as a German sixth, but resolved as a dominant seventh (or the reverse).

Example 1.5 Extended dominant chords

Despite theoretical attempts to classify the augmented sixth as an ‘approach chord’ to V or I6/4 there are many contexts in which this is patently not justifiable.⁹ Ex. 1.5 (c) shows a dominant chord with a sharpened fifth. The augmented fifth itself (D♯) is nearly always placed in the top voice and usually leads to the third of the tonic chord (E); this usage will be relatively familiar from the Romantic repertoire, where the augmented fifth characteristically leads to the reprise of a theme that begins on the third step of the scale. (This is, of course, only possible in major keys; the enharmonic equivalent in the minor key is the dominant thirteenth, Ex. 1.5 (e)). Haydn frequently wrote the augmented triad on V, and instances can be found in many of his earlier symphonies, often as part of the second-subject group or as a cadential motif. In his Symphony in...

Table of contents

• Cover Page
• Half Title page
• Dedication
• Title Page
• Copyright Page
• Contents
• List of Music Examples
• Preface
• Acknowledgements
• 1 Key Concepts
• 2 Natural Selection
• 3 Painted Words
• 4 Harmony and Invention
• 5 The Augmented Sixth in Bach's Music
• 6 The Science of Composition
• 7 Classical Contexts
• 8 Triumph and Ambiguity
• 9 Swansong
• Bibliography