Major and minor scales are the foundation of Western music theory. They're built using specific patterns of whole and half steps, creating distinct sounds and moods. Understanding these scales is crucial for composing, improvising, and analyzing music.

Scales also form the basis for key signatures, which indicate which notes are consistently altered in a piece. This knowledge helps musicians read, write, and transpose music accurately. Additionally, scales provide the building blocks for melody, harmony, and chord progressions across various musical genres.

Construction of major scales

• Major scales are one of the most fundamental building blocks in Western music theory and composition
• Constructed using a specific pattern of whole steps (W) and half steps (H) starting from any given note
• The formula for a major scale is W-W-H-W-W-W-H, which creates a bright and cheerful sound

Whole and half steps

• Whole steps are intervals that span two semitones or two adjacent keys on a piano (C to D)
• Half steps are intervals that span one semitone or two adjacent keys including black keys (C to C#)
• Understanding whole and half steps is crucial for constructing scales and understanding intervallic relationships

Sharps and flats

• Sharps (♯) raise a note by one half step, while flats (♭) lower a note by one half step
• When constructing scales, sharps and flats are used to maintain the proper interval pattern
• The key signature of a scale indicates which notes are consistently raised or lowered throughout the piece

Circle of fifths

• A visual representation of the relationships between keys, illustrating the progression of sharps and flats
• Moving clockwise around the circle adds one sharp to the key signature, while moving counterclockwise adds one flat
• Helps musicians understand key relationships and easily transpose music between keys

Construction of minor scales

• Minor scales have a darker, more somber sound compared to major scales and are commonly used in various musical genres
• There are three types of minor scales: natural, harmonic, and melodic, each with unique interval patterns and characteristics
• Minor scales are built starting from different scale degrees of their relative major scales

Natural minor

• Constructed by starting on the 6th scale degree of its relative major scale (A minor is the relative minor of C major)
• Follows the interval pattern W-H-W-W-H-W-W, creating a slightly different sound than the major scale
• Also known as the Aeolian mode, one of the seven church modes

Harmonic minor

• Differs from the natural minor scale by raising the 7th scale degree by one half step
• The raised 7th degree creates a stronger pull towards the tonic, especially when used in cadences
• Interval pattern: W-H-W-W-H-W½-H, with the augmented 2nd interval between the 6th and 7th degrees

Melodic minor

• Has two forms: ascending and descending
• Ascending form raises both the 6th and 7th scale degrees by one half step (W-H-W-W-W-W-H)
• Descending form is identical to the natural minor scale (W-W-H-W-W-H-W)
• The raised 6th and 7th degrees in the ascending form help to avoid the augmented 2nd interval found in the harmonic minor scale

Key signatures

• A key signature is a group of sharps or flats placed at the beginning of a staff, indicating which notes should be consistently raised or lowered throughout the piece
• Understanding key signatures is essential for reading, writing, and transposing music accurately
• The arrangement of sharps or flats in a key signature follows a specific order, which can be memorized using mnemonic devices

Sharps vs flats

• Key signatures can contain either sharps or flats, but never both
• The order of sharps is F♯, C♯, G♯, D♯, A♯, E♯, B♯ (mnemonic: "Father Charles Goes Down And Ends Battle")
• The order of flats is B♭, E♭, A♭, D♭, G♭, C♭, F♭ (mnemonic: "Battle Ends And Down Goes Charles' Father")

Determining key from signature

• The key of a piece can be determined by looking at the key signature and applying a few rules
• For sharp keys, the tonic is one half step above the last sharp in the key signature (D major has 2 sharps: F♯ and C♯)
• For flat keys, the tonic is the second-to-last flat in the key signature (E♭ major has 3 flats: B♭, E♭, and A♭)

Relative major and minor keys

• Every major key has a relative minor key that shares the same key signature
• The relative minor is located a minor 3rd (three half steps) below the tonic of the major key
• For example, A minor is the relative minor of C major, and both keys have no sharps or flats in their key signatures

Scale degrees and functions

• Scale degrees are the individual notes within a scale, each with a specific name and function
• Understanding scale degrees and their roles helps in analyzing and composing melodies and harmonies
• Scale degrees are often represented by Roman numerals (I, ii, iii, IV, V, vi, vii°) or Arabic numerals (1, 2, 3, 4, 5, 6, 7)

Tonic, dominant, and subdominant

• The tonic (1st degree) is the most stable and resolves tension, often used as the starting and ending point of a melody or harmony
• The dominant (5th degree) creates the strongest pull towards the tonic and is frequently used in cadences
• The subdominant (4th degree) acts as a counterbalance to the dominant and helps to establish the key

Leading tone in minor scales

• The leading tone is the 7th scale degree, which is one half step below the tonic
• In major scales, the leading tone is naturally present, but in minor scales, it must be raised to create a stronger pull towards the tonic
• The raised 7th degree is found in the harmonic and ascending melodic minor scales

Solfège syllables

• Solfège is a system of assigning syllables to scale degrees, helping musicians to sight-sing and recognize intervals by ear
• The syllables for major scales are: Do (1), Re (2), Mi (3), Fa (4), Sol (5), La (6), Ti (7)
• In minor scales, the syllables are modified to reflect the altered scale degrees: Do, Re, Me, Fa, Sol, Le, Te (harmonic minor) or Do, Re, Me, Fa, Sol, Le, La (melodic minor)

Modes and modal scales

• Modes are scales that are derived from the major scale by starting on different scale degrees
• Each mode has a unique interval pattern and characteristic sound, which can be used to create distinct melodies and harmonies
• There are seven main modes: Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, and Locrian

Ionian and Aeolian modes

• The Ionian mode is identical to the major scale, starting on the 1st scale degree (C-D-E-F-G-A-B)
• The Aeolian mode is identical to the natural minor scale, starting on the 6th scale degree (A-B-C-D-E-F-G)
• These two modes are the most commonly used in Western music and serve as the foundation for the other modes

Other church modes

• Dorian (2nd degree): Minor sound with a raised 6th degree, often used in jazz and folk music (D-E-F-G-A-B-C)
• Phrygian (3rd degree): Minor sound with a lowered 2nd degree, creating a Spanish or Middle Eastern flavor (E-F-G-A-B-C-D)
• Lydian (4th degree): Major sound with a raised 4th degree, giving a bright and dreamy character (F-G-A-B-C-D-E)
• Mixolydian (5th degree): Major sound with a lowered 7th degree, frequently used in rock and blues (G-A-B-C-D-E-F)
• Locrian (7th degree): Diminished sound with a lowered 2nd, 5th, and 7th degrees, rarely used in traditional harmony (B-C-D-E-F-G-A)

Parallel modes

• Parallel modes share the same tonic but have different interval patterns
• For example, C Ionian (C major) and C Aeolian (C natural minor) are parallel modes
• Changing from a major key to its parallel minor (or vice versa) is called a parallel modulation and can create an interesting shift in mood

Transposing melodies

• Transposition is the process of moving a melody or piece of music to a different key while maintaining its interval relationships
• Transposing is an essential skill for musicians, as it allows them to play in different keys and accommodate the ranges of various instruments or voices
• There are several methods for transposing melodies, including using interval relationships, scale degrees, and key signatures

Changing key signatures

• When transposing a melody to a new key, the key signature must be adjusted to maintain the proper interval relationships
• To determine the new key signature, count the interval between the original tonic and the new tonic, then apply that interval to the original key signature
• For example, transposing a melody from C major (no sharps or flats) to G major (1 sharp) requires adding one sharp to the key signature

Accidentals and chromatic alterations

• Accidentals are sharps, flats, or naturals that are used to temporarily raise, lower, or cancel the alteration of a note within a measure
• When transposing a melody with accidentals, the interval relationships between the notes must be maintained in the new key
• Chromatic alterations, such as secondary dominants or borrowed chords, should be transposed using the same interval relationships as the original melody

Modulation and tonicization

• Modulation is the process of changing from one key to another within a piece of music
• Tonicization is a brief emphasis on a new tonic, without fully establishing a new key
• When transposing a melody with modulations or tonicizations, the new key relationships must be carefully considered to ensure a smooth and musical transition

Scales in composition and improvisation

• Scales form the foundation of melody, harmony, and improvisation in various musical genres
• Understanding how to use scales effectively can help composers and improvisers create engaging and expressive music
• Different scales can evoke distinct emotions, moods, and cultural associations, allowing musicians to convey a wide range of ideas and feelings

Choosing scales for melody

• When composing or improvising a melody, the choice of scale can greatly influence the character and mood of the music
• Major scales are often used for bright, happy, or triumphant melodies, while minor scales can convey sadness, mystery, or introspection
• Modal scales, such as Dorian or Mixolydian, can add unique flavors and help to create memorable melodies that stand out from traditional major or minor tonalities

Harmony and chord progressions

• Scales provide the building blocks for harmony and chord progressions
• Chords are typically constructed using the 1st, 3rd, and 5th scale degrees (triads) or additional notes such as the 7th (seventh chords)
• By understanding the relationships between scales and chords, composers and improvisers can create harmonically rich and engaging progressions

Mood and emotional qualities of scales

• Different scales can evoke a wide range of emotions and moods in the listener
• Major scales are often associated with happiness, joy, and optimism, while minor scales can convey sadness, melancholy, or introspection
• Modal scales can create unique atmospheres, such as the mysterious and exotic sound of the Phrygian mode or the dreamy and uplifting character of the Lydian mode
• By carefully selecting scales and combining them in creative ways, composers and improvisers can take listeners on an emotional journey and effectively communicate their musical ideas