Unit 1: Key, Scales, and Modes

This study guide summarizes the Unit 1 concepts shown in the provided photos. It is a paraphrased review, not a transcription of the textbook.

Core Idea

Music in a key is organized around a central tone called the tonic. Other tones do not merely coexist with the tonic; they relate to it by degrees of stability, direction, and tendency. A scale is a compact way to show this tonal field: it starts from the tonic, moves through the available scale degrees, and returns to the tonic at the octave.

Key and Tonic

• A key has a tonic, the central tone around which the music is organized.
• Tones other than the tonic sound subordinate to it in different ways.
• Melodies often begin on tonic, mediant, or dominant, but tonal motion still tends to seek tonic as a point of rest or completion.
• The tonic may appear in different registers and still function as the same tonal center.

Scale Degrees

Scale degrees are numbered positions in a scale. Their traditional names are:

The octave is central to pitch organization: two notes with the same letter name but different registers sound closely related. This is called octave equivalence.

Major Scales

The major scale is a diatonic scale. It contains five whole steps and two half steps arranged in a specific pattern:

1 W 2 W 3 H 4 W 5 W 6 W 7 H 8

In major, the half steps occur between scale degrees 3-4 and 7-8. The half step from 7 to 8 gives scale degree 7 its leading-tone pull into tonic.

Stable and Active Tones

The tonic triad tones, scale degrees 1, 3, 5, and the octave 8, are relatively stable. They can serve as local goals in a melody. Other scale degrees are more active:

• 2 often connects 1 and 3.
• 4 often connects 3 and 5.
• 6 and 7 often connect 5 and 8.
• 7 has the strongest upward pull to 8 in major because it lies a half step below tonic.

Motion toward 1 has the greatest sense of finality, but motion toward 3 or 5 can also sound goal-directed because those notes belong to the tonic triad.

Passing and Neighboring Tones

A passing tone fills in stepwise motion between two more stable tones. For example, scale degree 2 can pass between 1 and 3, and scale degree 4 can pass between 3 and 5.

A neighboring tone leaves a stable tone by step and returns to the same stable tone. A neighbor above the stable tone is an upper neighbor; a neighbor below it is a lower neighbor.

These tones help explain why melodies feel like directed motion rather than a random sequence of notes.

Major and Minor

The most basic contrast between major and minor lies in the third above tonic:

• Major has a major third between 1 and 3.
• Minor has a minor third between 1 and 3.

The emotional meaning of major and minor is not absolute, but the major/minor contrast is still a major factor in the character of tonal music.

Natural Minor

Natural minor follows the key signature without raising scale degrees. Compared with major, it has lowered 3, 6, and 7:

1 W 2 H b3 W 4 W 5 H b6 W b7 W 8

Its half steps occur between 2-3 and 5-6. Because natural minor has a whole step between 7 and 8, scale degree 7 is called the subtonic rather than the leading tone.

Harmonic and Melodic Minor

Minor-key music often alters scale degrees 6 and 7 to strengthen tonal motion:

• Harmonic minor raises 7 so it can lead strongly to tonic.
• Melodic minor often raises both 6 and 7 in ascending motion, smoothing the approach to tonic.
• Descending melodic minor commonly returns 6 and 7 to their natural forms.

These are not separate minor keys. They are common forms or variants used within minor-key music. The key signature itself represents the natural minor collection.

Key Signatures

Major and minor keys use key signatures to preserve the correct pattern of whole and half steps.

• Moving upward by fifths adds sharps.
• Moving downward by fifths adds flats.
• Relative major and minor keys share a key signature but have different tonics.
• Parallel major and minor keys share a tonic but have different key signatures.

Examples:

• C major and A minor are relative keys.
• C major and C minor are parallel keys.

Modes

The seven diatonic modes are:

• Ionian, equivalent to the major scale
• Dorian
• Phrygian
• Lydian
• Mixolydian
• Aeolian, equivalent to natural minor
• Locrian

For common-practice tonal music, major and minor are the primary modes. Other modal colors may appear, but usually inside a broader major/minor tonal context.

Tonality

Tonality means organization around a tonal center. In a broad sense, any music organized around a central tone can be called tonal, including modal music and many non-Western traditions. In the common-practice context, the more specific idea is major-minor tonality: music organized primarily by major and minor keys.

Memory Targets

• Memorize the scale-degree names.
• Know the major scale whole/half-step pattern.
• Know the natural minor whole/half-step pattern.
• Know why natural minor has a subtonic and why raised 7 creates a leading tone.
• Memorize the fifteen major key signatures and fifteen minor key signatures.
• Be fluent with relative and parallel key relationships.
• Know the seven diatonic modes and which correspond to major and natural minor.