Which Method? Now that we know that there are four standard ways to move between chords whose roots lie a fifth apart (five if you count the doubled fifth), we need to think about which one we should use under any given circumstances. There is no universal answer. In general, they have been presented to you in the order in which they are most likely to occur in the work of the composers and voice-leading masters of the eighteenth century (especially J.S. Bach). This, therefore, is generally the order in which you should normally consider each possibility. However, each has its own characteristics that you will want to consider. The most important of these is the motion of the soprano; after that, we may need to consider specific types of internal motion that we are trying to promote (i.e., imitation), the effect that each method has on doubling (tripled roots or doubled fifths), and the effect that each method has on spacing (close, neutral, and open position).
Forward motion (down by fifth / up by fourth) Method Upper Voice Motion Types of Motion Doubling Spacing
Drawbacks
Common Tone (CT) 5↗3 3↗1 1→5 Steps
Similar Motion (SM) 5↘1 3 ↘↘ 5 1 ↘↘ 3 Two skips
Triple-Root (TR) 5↘1 3↗1 1→5 Steps
Tertian Leap (TL) 5↘1 3 ↘↘↘↘↘ 5 1→5 One leap
Doubled Fifth (DF) 5↗3 3 ↘↘ 5 1→5 One skip
Complete Triad in Top No effect
Complete Triad in Top No effect
Tripled Root
Complete Triad in Top Usually switches between open and close position
Doubled Fifth
Does not resolve –
2 1
Does not resolve – ; cannot be used when is in soprano.
7 1
7
Potentially moves to neutral position Can switch between open and close position in two moves, can create a voice exchange Should be left in same manner as approached. Best used at cadences.
Does not resolve – ; cannot be used when is in soprano.
7 1
7
Potential voice-crossing issues.
Potentially moves to neutral position Can switch between open and close position in two moves, can create a voice exchange Does not resolve – or – ; cannot be used when is in soprano; should be left in same manner as approached.
2 1
7 1 7
Accounting for Seventh Chords When we have seventh chords, we need to add a few details to our chart. First, the seventh must almost always resolve down, generally to the third of the following chord. Hence, any of the methods will work when this 7-3 is in the soprano (except the Tertian Leap, which is usually avoided because it creates a doubled third). Method Complete/ Incomplete Seventh replaces Correct resolution of tritone
Common Tone Usually incomplete 5
Similar Motion Usually complete 8
Triple-Root Complete
Doubled Fifth Complete
8
8
Yes
No
Yes
No
Tertian Leap
There is one extra concern when using a seventh chord. If the seventh chord begins as a triad, and the seventh is added partway through, any of the above methods will work; but if the seventh is to be part of the chord right from the beginning, the seventh itself should be approached by step or obliquely (we tend to be a bit flexible about this for the dominant seventh, but not for other types of sevenths). Hence, incomplete seventh chords should be approached by a motion in which the fifth is approached from above (i.e., similar motion), and complete seventh chords should be approached by motion in which the root is approached from below (i.e., common tone).
The Leading Tone and Tritones Up to now, it has been convenient to say that the leading tone always needs to resolve upwards. There are exceptions, and we can now be more specific: 1. The leading tone is always unstable when it is part of a dissonant chord, and should always resolve upwards in those cases (specifically, all types of diminished chords). 2. The leading tone is usually unstable when it is the root or third of a chord (i.e., , , and , etc.), and should usually resolve upwards (however, see below about tritones). 3. The leading tone is not unstable when it is the fifth of a consonant triad (i.e., ), and does not have to resolve upwards in this case. 4. The leading tone in either the melody or the bass can be used as a passing tone between and . This usually happens in a weak position, and may be harmonized by a weak dominant chord, which is understood as a passing chord; in this case, the passing motion overrules the resolution of the leading tone.
V V&
viio^
III
1
6
Tritones: diminished fifths should always resolve inward by step; augmented fourths should usually resolve outwards by step. 5. The leading tone is usually the bottom of a diminished fifth or the top of the augmented fourth. In either case, the preferred resolution is still up by step.
6. In some cases, if the note occurs as the top of the augmented fourth, it may resolve downwards instead of upwards, but this is not usually permitted when it occurs as the bottom of a diminished fifth. a. Hence, the similar motion method of resolving the dominant seventh chord is not necessarily the best choice when the seventh is high in the voicing. 7. The dominant seventh chord is a special case of a partially dissonant chord, in which the leading tone may resolve down if it is in an inner voice. However, as suggested in #6 above, it is still preferable for it to resolve upwards if it is part of a diminished fifth (rather than an augmented fourth). a. Notwithstanding this, the leading tone in other types of dissonant chords must still resolve upwards, regardless of the voice in which it is found.