Glossary
Acceptable Chords (Bass Line)
The specific triads (tonic, supertonic, subdominant, dominant) that are commonly used and expected in a well-formed bass line within common practice harmony.
Example:
When writing a bass line, stick to acceptable chords like I, IV, and V to ensure a strong harmonic foundation.
Alto
The second highest voice part in a four-part (SATB) texture, typically written in the treble clef with stems down.
Example:
The alto voice often fills in the harmony between the soprano and tenor, contributing to the chord's richness.
Bass
The lowest voice part in a four-part (SATB) vocal or instrumental texture, providing the harmonic foundation.
Example:
The bass line typically outlines the root of each chord, giving the harmonic progression its direction.
Cadence
A melodic or harmonic configuration that creates a sense of resolution or pause at the end of a musical phrase or section.
Example:
The piece concluded with a strong authentic cadence, providing a definitive sense of arrival on the tonic.
Chord Identification
The process of determining the root, quality (major, minor, etc.), and inversion of a given set of notes.
Example:
Accurate chord identification is crucial for understanding the harmonic progression of a piece.
Chord Positions
Refers to the vertical arrangement of the upper voices (soprano, alto, tenor) relative to each other, determining whether the chord is in open or closed spacing.
Example:
Understanding different chord positions helps in achieving varied textures and sounds within a four-part harmony.
Closed Position
A chord spacing where the upper three voices (soprano, alto, tenor) are as close together as possible, with no chord tones omitted between them.
Example:
A choir singing in closed position creates a dense, compact sound, often used for strong, unified harmonies.
Common Practice Period (CPP)
A historical era in Western music, roughly from 1650 to 1900, characterized by a standardized system of harmony, counterpoint, and form.
Example:
Many of the voice leading rules you learn in AP Music Theory are derived from the compositional practices of the Common Practice Period, as seen in works by Bach or Mozart.
Common Tones
Notes that are shared between two consecutive chords, often held in the same voice for smooth voice leading.
Example:
When moving from a C major chord to an E minor chord, the note E is a common tone that can be sustained in the same voice.
Contrary Motion
Two voices moving in opposite directions.
Example:
As the bass line descends, the soprano line ascends, creating a clear example of contrary motion.
Correct chord spelling
Ensuring that all notes present in a chord accurately represent its theoretical construction (e.g., a C major triad must contain C, E, and G).
Example:
Before analyzing a progression, always check for correct chord spelling to confirm you're identifying the harmony accurately.
Cross-Relations
A voice leading error where a chromatic alteration of a note appears in one voice immediately after its diatonic version appeared in another voice.
Example:
Having an F# in the soprano followed by an F natural in the alto in the next chord would create an undesirable cross-relation.
Dissonances
Musical intervals or chords that create a sense of tension, instability, or clashing, often requiring resolution to consonance.
Example:
The composer used a striking dissonance in the harmony to create a moment of intense drama before resolving to a peaceful chord.
Doubling
The practice of repeating a specific note of a chord in a different octave or voice within the same harmony.
Example:
In a C major triad, doubling the root (C) is common, often placing one C in the bass and another in an upper voice.
Educated Guesses
In the context of analysis, making informed assumptions about chords or voice leading based on common practice rules and typical progressions when direct identification is unclear.
Example:
When unsure about a specific chord, making educated guesses based on the surrounding harmonies can often lead to the correct answer.
Fermatas
A musical symbol indicating that a note or rest should be held for an indefinitely prolonged duration, often marking the end of a phrase or section.
Example:
In a chorale, a fermata over the final chord signals a complete stop and the end of the musical phrase.
Harmonic Sense (Bass Line)
The quality of a bass line where its notes logically support and define the underlying chord progression.
Example:
A good bass line always makes harmonic sense, clearly outlining the roots or inversions of the chords.
Independence of voices
The quality where each voice in a polyphonic texture maintains its own distinct melodic contour and rhythmic identity.
Example:
In a fugue, the independence of voices is paramount, as each melodic line weaves in and out, creating complex counterpoint.
Leading Tone Doubling
The voice leading rule that prohibits doubling the leading tone in a chord, as it has a strong tendency to resolve.
Example:
To ensure proper leading tone resolution, avoid leading tone doubling in any voice, especially the outer ones.
Leading Tone Resolution
The tendency of the leading tone (the seventh scale degree) to resolve upward by a half step to the tonic.
Example:
In G major, the F# (leading tone) must exhibit leading tone resolution by moving up to G in the next chord.
Leaps (Bass Line)
Larger melodic intervals (greater than a step) that are more common and acceptable in the bass line compared to upper voices.
Example:
The bass line often uses leaps of a perfect fifth or octave to clearly define chord changes.
Linear smoothness
The characteristic of individual melodic lines moving primarily by step or small leaps, avoiding large, disruptive jumps.
Example:
A well-written soprano line exhibits linear smoothness, making it easy and pleasant to sing.
Melodic Interest (Bass Line)
The characteristic of a bass line having a balanced contour of upward and downward motion, steps, and appropriate leaps to create an engaging melodic shape.
Example:
Beyond just outlining chords, a bass line should have melodic interest, making it a compelling line in its own right.
Melodic Intervals
The distance between two successive notes in a single melodic line.
Example:
Acceptable melodic intervals for good voice leading typically include seconds, thirds, perfect fourths, and perfect fifths.
Oblique Motion
One voice remains stationary while another voice moves.
Example:
When a sustained pedal tone is held in the bass while the upper voices move, it creates oblique motion.
Octave Leaps (Bass Line)
A melodic leap of a perfect octave in the bass line, which should typically be followed by a change in melodic direction.
Example:
After an octave leap from C3 to C4, the bass line then moved down to G3, changing direction as expected.
Open Position
A chord spacing where the upper three voices (soprano, alto, tenor) are spread out, allowing for more space between them.
Example:
The use of open position in the string quartet gave the chord a more resonant and spacious quality.
Parallel Fifths
A voice leading error where two voices move in parallel motion, both forming a perfect fifth interval, from one chord to the next.
Example:
Composers generally avoid parallel fifths because they can make the harmony sound hollow or static.
Parallel Motion
Two voices moving in the same direction by the exact same interval.
Example:
Singing a melody in unison with a friend is an example of parallel motion at the octave.
Parallel Octaves
A voice leading error where two voices move in parallel motion, both forming a perfect octave interval, from one chord to the next.
Example:
The prohibition against parallel octaves ensures that each voice maintains its melodic independence rather than simply doubling another.
Repeated Bass Notes
The acceptable practice of repeating the same note in the bass line, often on strong beats or as part of a suspension.
Example:
The composer used repeated bass notes on the tonic to emphasize the stability of the home key.
Repeated Harmonies (Bass Line)
The practice of repeating the same chord, often on strong beats or at the beginning of a phrase, which is acceptable in bass line writing.
Example:
The bass line used repeated harmonies on the downbeats, giving the progression a steady, rhythmic pulse.
Rhythm (Bass Line)
The duration and pattern of notes in the bass line, commonly using quarter notes but also incorporating half and eighth notes.
Example:
The rhythm of the bass line was steady, mostly quarter notes, providing a solid foundation for the faster upper voices.
SATB
An acronym representing the four standard voice parts in choral writing: Soprano, Alto, Tenor, and Bass, ordered from highest to lowest.
Example:
Most four-part harmony exercises in AP Music Theory require writing in SATB format, ensuring proper voice leading for each part.
SATB Order (Voice Crossing)
Maintaining the standard vertical arrangement of voices (Soprano, Alto, Tenor, Bass) to prevent one voice from sounding lower than the voice immediately below it.
Example:
To avoid awkward voice crossing, ensure the alto never sings below the tenor, maintaining proper SATB order.
Similar Motion
Two voices moving in the same direction, but by different intervals.
Example:
If the soprano moves up a third while the alto moves up a step, they are exhibiting similar motion.
Soprano
The highest voice part in a four-part (SATB) vocal or instrumental texture.
Example:
The soprano often carries the main melody in a chorale, making it a crucial line to analyze for melodic motion.
Spacing
The vertical distance between the notes of a chord, determining whether it sounds open or compact.
Example:
The spacing of the choir's chords created a rich, resonant sound, with notes spread evenly across the vocal range.
Stepwise Motion
Melodic movement primarily by steps (intervals of a second), creating a smooth and connected line.
Example:
Most well-written melodies feature a lot of stepwise motion, making them easy to follow and sing.
Tenor
The second lowest voice part in a four-part (SATB) texture, typically written in the bass clef with stems up.
Example:
The tenor line can sometimes mirror the bass or provide a counter-melody, adding depth to the inner voices.
Triad Leaps (Bass Line)
Successive melodic leaps in the bass line that collectively outline the notes of a specific triad.
Example:
The bass line moved C-E-G, demonstrating triad leaps that clearly outlined a C major chord.
Tritone
A dissonant interval spanning three whole steps, often found as an augmented fourth or diminished fifth, which typically requires careful resolution.
Example:
The tritone from F to B creates a strong tension that often resolves to a consonant interval like a major third.
Voice leading
The art of creating smooth and logical melodic lines for each individual voice within a chord progression, ensuring pleasing transitions between harmonies.
Example:
When composing a hymn, careful voice leading ensures that each singer's part flows naturally from one note to the next, avoiding awkward jumps.