Overview
This lecture provides a comprehensive crash course in the basics of music theory, covering notes, scales, chords, chord progressions, melodies, and rhythm, with practice exercises to help internalize each concept.
What is Music Theory?
- Music theory is the language and system for understanding, interpreting, and communicating about music.
- It helps you make sense of chords, notes, melodies, and rhythms, becoming natural with practice.
- Mastery of theory allows for fluid music creation and learning new concepts faster.
Notes, Octaves, and Scales
- Music primarily uses twelve notes, named A–G with sharps (♯) and flats (♭).
- Black keys on a keyboard are sharps (higher) or flats (lower) relative to white keys.
- An octave is the interval between two notes with the same name whose frequency differs by a factor of two.
- A semitone (half-step) is the interval between adjacent notes; two semitones make a whole tone.
- A key is a set of notes that sound good together; the most common keys are major and minor, each using seven notes.
- A scale is a sequence of notes in a key, e.g., the C major scale is all white keys: C D E F G A B.
Building Scales and Naming Notes
- The major scale formula is: whole, whole, half, whole, whole, whole, half steps.
- Notes in a scale are numbered as scale degrees (1=root, 2=second, etc.).
- Each scale uses each letter name once; sharps or flats are chosen for clarity.
Chords and Triads
- Chords are multiple notes played together, forming the song’s harmonic foundation.
- The basic chord (triad) uses the root, third, and fifth degrees of the scale.
- Major triad formula: 4 semitones (root to third), then 3 semitones (third to fifth).
- Minor triad formula: 3 semitones, then 4 semitones.
Keys, Scale Degrees, and Chord Progressions
- Scale degrees are used to number and identify chords in any key, allowing flexible chord progression writing.
- The pattern for triads in a major scale is: major, minor, minor, major, major, minor, diminished.
- Chord progressions are sequences of these chords, e.g., I–V–vi–IV (1–5–6–4).
- Roman numerals represent scale degrees (uppercase for major, lowercase for minor).
Inversions and Voice Leading
- An inversion changes which note is lowest in a chord, making transitions between chords smoother.
- Using inversions can make chord progressions sound more connected and natural.
Melodies and Pentatonic Scales
- Melodies are single-note sequences that fit over chords, balancing tension and stability.
- Melodies often use both chord notes and passing notes not in the chord.
- The major pentatonic scale removes the 4th and 7th degrees, making it easy to create pleasing melodies.
Rhythm and Counting
- Music is organized into bars (measures) with beats typically counted in groups of four.
- Note durations are whole, half, quarter, eighth, and sixteenth notes.
- Rhythm is subdivided as 1, 1-and, 1-e-and-a, etc., for increasing resolution.
- Writing rhythms in this system helps with playing, composing, and memorizing music.
Key Terms & Definitions
- Note — A sound with a specific pitch.
- Octave — Interval between two identical notes at different pitches (frequency doubled).
- Semitone/Half-step — Smallest interval between two adjacent notes.
- Scale — Ordered sequence of notes in a key.
- Key — Group of notes forming a musical basis.
- Triad — Three-note chord (root, third, fifth).
- Chord Progression — Sequence of chords within a key.
- Inversion — Reordering chord notes so a note other than the root is lowest.
- Pentatonic Scale — Five-note scale formed by omitting the 4th and 7th degrees.
- Bar/Measure — A segment of music containing a fixed number of beats.
Action Items / Next Steps
- Practice building major scales using the whole/half-step formula.
- Name all scale degrees and their notes in various keys.
- Create triads on the first six degrees of different major scales, labeling major or minor.
- Compose random chord progressions using scale degree numbers in any key.
- Experiment with chord inversions for smoother transitions.
- Write and play melodies using both full and pentatonic scales over your chord progressions.
- Transcribe the rhythm of a melody or drum beat from a favorite song using sixteenth-note notation.