B Added 9th Chord
Chord Tones: B Added 9th Chord
Symbol: add9, add2 — Formula: 1-3-5-9
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | B4 | 493.883 Hz |
| 3 | D♯4 | 311.127 Hz |
| 5 | F♯4 | 369.994 Hz |
| 9 | C♯4 | 277.183 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | Badd9 |
| All Common Symbols | add9, add2 |
| Interval Formula | 1-3-5-9 |
| Harmonic Category | bright |
Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.
Inversions
| Inversion | Notes (low to high) | Bass Note | Slash Notation |
|---|---|---|---|
| Root Position | B4 – D♯4 – F♯4 – C♯4 | B | B Added 9th Chord |
| First Inversion | D♯4 – F♯4 – C♯4 – B4 | D♯ | B Added 9th Chord/D♯ |
| Second Inversion | F♯4 – C♯4 – B4 – D♯4 | F♯ | B Added 9th Chord/F♯ |
| Third Inversion | C♯4 – B4 – D♯4 – F♯4 | C♯ | B Added 9th Chord/C♯ |
Harmonic Function
The B add9 chord commonly functions as the leading tone (vii) in C major or dominant (V) in E major. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.
The add9 chord adds a ninth (octave + second) to a major triad without including the seventh. It has a bright, open sound, richer than a plain major chord but less complex than a major ninth. The B Added 9th Chord specifically contains 4 notes: B, D♯, F♯, C♯ (formula: 1-3-5-9). On guitar, B-rooted chords are typically played as barre chords at the second or seventh fret, and on piano they use a comfortable mix of black and white keys. K-pop, J-pop, and modern R&B productions frequently feature B-rooted chords, chosen for how the key sits within typical vocal ranges.
Common Progressions
The B Added 9th Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
Songs Featuring the Added 9th Chord
Well-known songs where the B Added 9th Chord — or this chord type — plays a prominent role:
- Every Breath You Take – The Police
- With or Without You – U2
- Right Here Waiting – Richard Marx
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| B4 | 493.883 Hz | 495.000 Hz | 490.548 Hz |
| D♯4 | 311.127 Hz | 309.026 Hz | 313.951 Hz |
| F♯4 | 369.994 Hz | 371.251 Hz | 367.911 Hz |
| C♯4 | 277.183 Hz | 278.437 Hz | 279.067 Hz |
Scales Containing the B Added 9th Chord
These scales include the B Added 9th Chord as a diatonic or characteristic chord: