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| Most frequent/important way of expanding ANY major/minor triad | (Chords can also be extended by changing tones solely in the soprano line) Is by moving the bass between the root and 3rd of the chord= This changes the position of the chord from [5/3] to [6/3] (or the reverse)= In this context, [6/3] functions as in inversion of [5/3]= |
| [6/3] expanding [5/3] | Parallel 10ths (between the outer voices) and Voice Exchange (interchanging 2 tones between 2 voices) |
| Doubling I^6 | Any tone may be doubled= Doubling the soprano often gives a good sonority |
| Doubling V^6 | The leading tone (scale degree 7) must NEVER be doubled= Both the remaining tones of V^6 (scale degrees 2 and 5) are possible choices |
| [6/3] substituting for [5/3]=GOOD/OK | I^6 and V^6 can support the same melody tones as I and V= They imply the same harmonic function (though less strongly)= They can thus substitute for [5/3] in some circumstances (EX: I^6 can replace I where the greater stability of the root position chord is not needed |
| [6/3] substituting for [5/3]=BAD/NOT OK | [6/3] chords sound much less stable (i.e. sound more "flowing") than do their root-position equivalents [5/3]= REASON: The 6th (the most characteristic interval of the [6/3] chord) is a much less stable sound than is the 5th (which occurs in root position)= RESULT: Where stability is needed (e.g. beginnings & endings), [6/3] is NOT a satisfactory substitute for [5/3] |
| Limitation of I^6 | Avoid the progression {V^7}-{I^6} |
| V^7-I^6 | AVOID this progression= REASON: In simple textures, the resolution of the 7th of V^7 (scale degrees 4-3) combined with the bass motion of scale degrees 5-3 creates a bad set of HIDDEN OCTAVES (particularly if I^6 is in a rhythmically strong position) |
| I-I^6-V | A bass motion from I to V can land on scale degree 3 along the way= If tonic harmony is sustained above the s.d. 3 (i.e. if the harmony does not change), then a I^6 chord will result= Although the harmony changes from I to V, the bass line ARPEGGIATES the tonic triad, a feature that helps the listener relate the whole progression to the governing tonic= Easiest way to accomplish this arpeggiation is to move up from s.d.'s 1 to 3 and 3 to 5 (HOWEVER, a motion down a 6th from I to I^6 is also possible) |
| I-I^6-V-I | Continuing on to I produces a larger arpeggiation and one that sounds more self-contained (ending as it does on the tonic note)= Bass arpeggiations like these are an important way of expanding the initial tonic harmony of the basic I-V-I progression |
| I-V^6-I | (Using V^6 between two root-position tonics...) Produces the stepwise bass line s.d.'s 8-7-8 and makes possible a contrapuntal expansion of tonic harmony= Here the specific function of V^6 is that of a NEIGHBORING CHORD |
| I-V^6-I: When should V be used instead of V^6? | When a clear expression of the harmonic 5th relationship is needed (as in most cadences), root-position V should appear (but in other situations, especially near the beginning or the middle of phrases, V^6 often functions more effectively) |
| Uses of V^6 within an expanded tonic (i.e. in the progression I-V^6-I) | You can have V^6 support s.d. 2 in a rising soprano line (i.e. s.d's 1-2-3) which often occurs at the beginning of a phrase= You can have V^6 from an effecitve support for s.d. 5 in the soprano (the stepwise motion in the bass from 8-7-8 allows the jumpiness of the soprano) |
| In what progression can I^6 replace I? | I^6 can replace the initial tonic in the progression I-V^6-I= Here, the bass of V^6 functions as an incomplete neighbor to I= In minor, the progression produces a perfectly good diminished 4th in the bass line= Because s.d. 7 is active in the direction of s.d. 8, V^6 normally continues on to I[5/3], NOT I^6 |
| Expanding [6/3] | Brief expansions of [6/3] chords occur fairly often (can expand by going from [6/3] to [5/3] back to [6/3])= HOWEVER, for large-scale expansions (where the chord becomes the basis of an entire section), the stable sonority of the ROOT POSITION is necessary |
| Describe a bass line that expands tonic harmony? How can this bass line take on a more melodic character? | A bass line that expands tonic harmony by moving from s.d.'s 1 to 3 (or from 3 to 1) can take on a more melodic character by passing through s.d. 2 (e.g. 1-2-3 OR 3-2-1)= The passing s.d. 2 can become more prominent if it forms part of a chord (in this case, we speak of a PASSING CHORD [i.e. VII^6]) |
| VII^6 | Is a useful PASSING CHORD built on s.d. 2= Contains the three upper tones of V^7 and (like it) can support s.d.'s 7, 2, and 4 in the soprano |
| I^6-VII^6-I | VII^6 leads from I^6 to I= The two stepwise motions to s.d. 1 (from the adjacent pitches s.d.'s 2 and 7) combine with the descent of s.d.'s 4 to 3 and produce a strong sense of directed motion= Because of the stepwise bass (however), VII^6 functions more typically as a melodic, contrapuntal chord than a cadential, harmonic one |
| I-VII^6-I^6: Outer-Voice possibilities for a VII^6 that passes from I to I^6 | (SIDE NOTE: Notice that VII^6 can be used for a descending melodic bass line in I^6-VII^6-I [s.d. 3-2-1] or an ascending melodic bass line in I-VII^6-I^6 [s.d. 1-2-3]) Very often (as with I-I^6 or I^6-I), the SOPRANO will form parallel 10ths or a voice exchange with the bass= Because the soprano moves by step between two tones of the I chord, it participates in expressing the expanded tonic harmony= THUS, both outer voices join forces to create a counterpoint that animates an extended or PROLONGED tonic= Because it produces stepwise motion in the bass and permits it to occur in the soprano as well, VII^6 effects a contrapuntal expansion of the disjunct, arpeggiated progressions |
| VII^6= Other important function (besides its basic function of passing between I and I^6) | VII^6 can form a NEIGHBORING CHORD to I or I^6 |
| Doubling VII^6 | Usually best to double the bass tone (s.d. 2) because this is not part of the tritone= However, voice-leading considerations may make doubling s.d. 4 preferable= The LEADING TONE (s.d. 7) must NEVER be doubled |
| VII^6: What does it contain? | Contains an augmented 4th or diminished 5th in the upper voices= Because the bass of VII^6 is consonant with both the other tones, the effect of the dissonance is considerably softened |
| Resolution of VII^6 | s.d. 7 to 8 and 4 to 3 |
| Resolution of VII^6: Dissonance of an Augmented 4th | If the dissonance (in chord when written out) is an augmented 4th, it can move to a Perfect 4th (s.d. 4 moving UP to 5) |
| Resolution of VII^6: Dissonance of a Diminished 5th | Moving s.d. 4 up to 5 produces the problematic interval succession d5-P5= Bach resolves the diminished 5th normally when VII^6 moves to I[5/3]= However, if VII^6 moves to I^6, Bach often allows s.d. 4 to move up to 5= In this situation, s.d. 3 (the tone of resolution), is transferred into the bass, where it forms a very prominent element of the chord, and the parallel 10ths above the bass make for a fluent progression |
| VII^6: d5-P5 | Bach doubles s.d. 4 (a strategy that allows resolution of one of the tritones, stepwise voice leading, and a complete chord= If doubling s.d. 4 results in both a diminished 5th and an augmented 4th, resolve the diminished 5th |
| ***If VII^6 goes to I^6... | (Scale Degree 7 will normally move to 8) It is not necessary for the tritone to resolve (s.d. 4 may move to 5) |
| ***If VII^6 goes to I[5/3]... | (Scale Degree 7 will normally move to 8) The tritone must resolve if it is a diminished 5th= However, if it is an augmented 4th, s.d. 4 may move to 5 |
| VII[5/3] vs. VII^6 | VII[5/3] occurs much less frequently than VII^6 because of the dissonance (diminished 5th) involving the bass |
