Chapter 9: Triads in 2nd Inversion & Part Writing

 

 

 

 

 

Second inversion triads are unstable, and should be used with caution.

 

*Chord contains interval of a fourth

 

*Second-inversion is usually found in the tonic chord, but less common in all others.

 

 

 

 

Second-inversion triads should only be used when...

 

Cadential	The tonic 6/4 chord resolves to the V chord at the cadence. Used in this way, the 6/4 chord is a decoration of the V chord.	Bass note is doubled
Passing Bass	The bass note(^V) of the 6/4 chord acts as a PT. the passing bass may be found as a tonic 6/4 between IV and IV^6 chords or as a dominant 6/4 between the I and I^6 chords.	Bass is doubled
Arpeggiated Bass	The bass note(^V) participates in an arpeggiation of the smae chord. Usage of the 6/4 chords occurs occasionally with triads other than the tonic.	Bass is doubled
Pedal Bass	a.k.a. stationary bass or neighboring tone chords, the bass note is preceded and follwed by the same tone and is interspersed between two root positions of the same triad. This type also occurs occasionally with the IV6/4 as well as the tonic.	Bass is doubled

 

 

 

 

Summary of Stylistic Practices for 6/4 chords.

 

*Unless you can't, always double the bass.

 

*Approach and leave 6/4 chords as stepwise as possible.

 

*In arpeggiated 6/4 chords the bass note is approached or left by skip.

 

*Only use four types listed above.

 

 

 

 

 

There are no exceptions to these practices under any conditions

 

1. NO parallel 8, 5, or 1. (Remember, we dont want Bach killing kittens!)
2. NEVER double the leading tone.
3. DO NOT write pitches out of range for a particular voice.
4. Avoid auggie 2s (A2) and auggie fourths (A4)

 

 

 

 

 

 

 

 

When you're locked in a corner:

 

• Avoid crossing voices.

Only time justified is when it provides voice leading

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• Spacing between voices should not exceed an octave

Except between Bass and Tenor (never greater than two octaves)

• Do Not overlap two adjacent voices (S-A, A-T, T-B) more than a whole step

Overlaps of a half or whole step may be employed if it improves voice leading

• Do Not move in same direction to perfect intervals in the two outer voices (sop and bass)

Motion creates parallel perfect intervals

• Unequal 5ths, P5s to d5ths, should be used sparingly.

The progression vii°6 to I, in some circumstances, requires use of unequal fifths

• Melodic augmented 2nds and 4ths are almost never found in choral literature.

a. descen. d5th appers sometimes in bass, rarely in sop

b. d4th is a diatonic interval in harmonic minor scale + may be written in isolated situations

• Leading tone should progress up to tonic when in an outer voice (Sop or Bass)