Glossary
6/4 Chords
A triad in second inversion, meaning the fifth of the chord is in the bass. They are generally considered weak and function as embellishments rather than structural harmonies.
Example:
A C major chord with G in the bass (C/G) is a C major 6/4 chord.
Arpeggiated 6/4 Chords
6/4 chords used to harmonize an arpeggiated bass line, where the bass plays notes of a single chord in sequence. The upper voices often sustain.
Example:
A C major chord followed by a C/E (I6) and then a C/G (I 6/4) where the bass plays C-E-G is an arpeggiated 6/4 chord progression.
Arpeggio
A broken chord where the individual notes of a chord are played in succession rather than simultaneously. It creates a flowing, melodic effect.
Example:
Playing C-E-G-C upwards on a piano is an arpeggio of a C major chord.
Cadential 6/4
A specific type of I 6/4 chord that occurs immediately before a V chord at a cadence. It functions as a dominant embellishment, despite being named a tonic chord.
Example:
In G Major, a C/G chord (I 6/4) resolving to a D major chord (V) at the end of a phrase is a classic cadential 6/4.
Embellishments
Musical elements, such as non-chord tones or certain chords, that decorate or elaborate a melodic line or harmonic progression without altering its fundamental structure. 6/4 chords often serve this purpose.
Example:
A composer might use a neighboring 6/4 chord as an embellishment to add color around a stable tonic harmony.
Neighboring (Pedal) 6/4 Chords
A 6/4 chord where the bass note remains constant while the upper voices move to neighboring tones and then return to the original chord tones. It embellishes a single harmony.
Example:
In F Major, a Bb/F chord (IV 6/4) occurring between two F major chords (I) with the bass staying on F is a neighboring 6/4 chord.
Passing 6/4 Chords
A 6/4 chord that connects two other chords stepwise in the bass line, often occurring on a weak beat. It functions as a melodic bridge.
Example:
A progression like C - G/B - Am (I - V6/4 - vi) where the bass moves C-B-A uses a passing 6/4 chord.
Passing Tone
A non-chord tone that connects two chord tones stepwise, typically occurring on a weak beat. It creates melodic motion between stable harmonies.
Example:
In a C major scale, the note D between C and E can function as a passing tone.
Root position viio chords
A diminished triad built on the leading tone of a scale, with the root in the bass. These are generally avoided in common practice harmony due to their inherent instability and voice leading challenges.
Example:
In C Major, a B diminished triad (B-D-F) with B in the bass is a root position viio chord, which is typically avoided.
Stepwise Motion
Melodic movement where notes move by a step (a half step or whole step) to an adjacent scale degree. This creates smooth and conjunct lines.
Example:
A melody moving from C to D to E demonstrates stepwise motion.
Unacceptable Progressions
Harmonic progressions that are generally avoided in common practice harmony due to poor voice leading, weak harmonic direction, or creating undesirable sounds.
Example:
A V-IV progression is often considered an unacceptable progression because it moves backward in the typical T-PD-D-T harmonic flow.
Voice Leading
The melodic and harmonic movement of individual musical lines (voices) within a polyphonic texture. Good voice leading ensures smooth and logical progression.
Example:
Avoiding parallel octaves and fifths is a fundamental rule of good voice leading.
Weak Beat
A beat in a measure that receives less rhythmic emphasis or stress compared to a strong beat. 6/4 chords, especially passing ones, often occur on weak beats.
Example:
In 4/4 time, beats 2 and 4 are typically considered weak beats.
Weak Chords
Chords that generally sound unstable or less conclusive, often used to decorate or connect stronger harmonies rather than providing harmonic foundation. 6/4 chords are typically considered weak.
Example:
In a progression, a weak chord like a passing 6/4 might connect two root-position triads, adding melodic interest without strong harmonic drive.
iii6 chords
A mediant triad in first inversion. Similar to vi6, these chords are uncommon in common practice harmony and usually signal a mistake.
Example:
In C Major, an E minor chord with G in the bass (Em/G) is a iii6 chord, which is generally avoided in typical harmonic progressions.
vi6 chords
A submediant triad in first inversion. These chords are generally rare and often indicate an error in common practice harmony exercises.
Example:
In C Major, an A minor chord with C in the bass (Am/C) is a vi6 chord, which is typically avoided in standard part-writing.