Inti teori musik dalam satu halaman: not, interval, rumus akor dan tangga nada, tanda kunci, dan pola akor diatonis untuk setiap kunci.
Musik Barat menggunakan 12 nada per oktaf, berjarak satu semiton. Not tuts hitam memiliki dua nama (ekuivalen enharmonis) — mana yang digunakan bergantung pada kuncinya.
| Semiton | Simbol | Interval | Inversi |
|---|---|---|---|
| 0 | P1 | Perfect Unison | P8 |
| 1 | m2 | Minor Second | M7 |
| 2 | M2 | Major Second | m7 |
| 3 | m3 | Minor Third | M6 |
| 4 | M3 | Major Third | m6 |
| 5 | P4 | Perfect Fourth | P5 |
| 6 | TT | Tritone | TT |
| 7 | P5 | Perfect Fifth | P4 |
| 8 | m6 | Minor Sixth | M3 |
| 9 | M6 | Major Sixth | m3 |
| 10 | m7 | Minor Seventh | M2 |
| 11 | M7 | Major Seventh | m2 |
| 12 | P8 | Perfect Octave | P1 |
| Simbol | Not (dari C) | Semiton |
|---|---|---|
| C | C, E, G | 0–4–7 |
| Cm | C, E♭, G | 0–3–7 |
| C+ | C, E, G♯ | 0–4–8 |
| C° | C, E♭, G♭ | 0–3–6 |
| Csus2 | C, D, G | 0–2–7 |
| Csus4 | C, F, G | 0–5–7 |
| C5 | C, G | 0–7 |
| C6 | C, E, G, A | 0–4–7–9 |
| C6m | C, E♭, G, A | 0–3–7–9 |
| C7 | C, E, G, B♭ | 0–4–7–10 |
| CM7 | C, E, G, B | 0–4–7–11 |
| Cm7 | C, E♭, G, B♭ | 0–3–7–10 |
| Co7 | C, E♭, G♭, B♭♭ | 0–3–6–9 |
| CM9 | C, E, G, B, D | 0–4–7–11–14 |
| Cm9 | C, E♭, G, B♭, D | 0–3–7–10–14 |
| Tangga nada | Langkah | Contoh dari C |
|---|---|---|
| Major (Ionian) | W–W–H–W–W–W–H | C, D, E, F, G, A, B |
| Natural Minor (Aeolian) | W–H–W–W–H–W–W | C, D, E♭, F, G, A♭, B♭ |
| Harmonic Minor | W–H–W–W–H–W+H–H | C, D, E♭, F, G, A♭, B |
| Melodic Minor | W–H–W–W–W–W–H | C, D, E♭, F, G, A, B |
| Dorian | W–H–W–W–W–H–W | C, D, E♭, F, G, A, B♭ |
| Phrygian | H–W–W–W–H–W–W | C, D♭, E♭, F, G, A♭, B♭ |
| Lydian | W–W–W–H–W–W–H | C, D, E, F♯, G, A, B |
| Mixolydian | W–W–H–W–W–H–W | C, D, E, F, G, A, B♭ |
| Locrian | H–W–W–H–W–W–W | C, D♭, E♭, F, G♭, A♭, B♭ |
| Major Pentatonic | W–W–W+H–W–W+H | C, D, E, G, A |
| Minor Pentatonic | W+H–W–W–W+H–W | C, D♯, F, G, A♯ |
| Blues | W+H–W–H–H–W+H–W | C, D♯, F, F♯, G, A♯ |
| Tanda kunci | Kunci mayor | Kunci minor |
|---|---|---|
| — | C Mayor | A Minor |
| 1♯ | G Mayor | E Minor |
| 2♯ | D Mayor | B Minor |
| 3♯ | A Mayor | F♯ Minor |
| 4♯ | E Mayor | C♯ Minor |
| 5♯ | B Mayor | G♯ Minor |
| 6♯ | F♯ Mayor | D♯ Minor |
| 7♯ | C♯ Mayor | A♯ Minor |
| 1♭ | F Mayor | D Minor |
| 2♭ | B♭ Mayor | G Minor |
| 3♭ | E♭ Mayor | C Minor |
| 4♭ | A♭ Mayor | F Minor |
| 5♭ | D♭ Mayor | B♭ Minor |
| 6♭ | G♭ Mayor | E♭ Minor |
| 7♭ | C♭ Mayor | A♭ Minor |
Urutan kres: F♯ C♯ G♯ D♯ A♯ E♯ B♯. Urutan mol: B♭ E♭ A♭ D♭ G♭ C♭ F♭. Minor relatif selalu tiga semiton di bawah kunci mayornya.
| Derajat | I | ii | iii | IV | V | vi | vii° |
|---|---|---|---|---|---|---|---|
| Kunci mayor | maj | min | min | maj | maj | min | dim |
| Derajat | i | ii° | III | iv | v | VI | VII |
|---|---|---|---|---|---|---|---|
| Kunci minor | min | dim | maj | min | min | maj | maj |
Mulailah dengan 12 not dan interval, lalu tangga nada mayor beserta tanda kuncinya, kemudian trinada dan pola akor diatonis. Segala hal lainnya — mode, akor septim, progresi — dibangun di atas keempat blok itu.
Bangun sebuah trinada pada masing-masing tujuh derajat tangga nada hanya dengan menggunakan not tangga nada tersebut. Dalam setiap kunci mayor, kualitasnya mengikuti pola yang sama: mayor, minor, minor, mayor, mayor, minor, diminished.
Untuk kres, kuncinya berada setengah langkah di atas kres terakhir; untuk mol, kuncinya dinamai berdasarkan mol kedua dari terakhir. Minor relatif berada tiga semiton di bawah kunci mayor.