B Dominant Ninth Chord
Chord Tones: B Dominant Ninth Chord
Symbol: 9 — Formula: 1-3-5-♭7-9
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | B | 493.883 Hz |
| 3 | D# | 311.127 Hz |
| 5 | F# | 369.994 Hz |
| ♭7 | A | 440.000 Hz |
| 9 | C# | 277.183 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | B9 |
| All Common Symbols | 9 |
| Interval Formula | 1-3-5-♭7-9 |
| Harmonic Category | tense |
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 | B – D# – F# – A – C# | B | B Dominant Ninth Chord |
| First Inversion | D# – F# – A – C# – B | D# | B Dominant Ninth Chord/D# |
| Second Inversion | F# – A – C# – B – D# | F# | B Dominant Ninth Chord/F# |
| Third Inversion | A – C# – B – D# – F# | A | B Dominant Ninth Chord/A |
| Fourth Inversion | C# – B – D# – F# – A | C# | B Dominant Ninth Chord/C# |
Harmonic Function
The B dominant ninth 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 dominant ninth chord extends the dominant seventh with a ninth, adding color and richness to one of music's most harmonically active chords. Essential in jazz, blues, and funk.
Common Progressions
The B Dominant Ninth Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
V9-Iii9-V9-I
Songs Featuring the Dominant Ninth Chord
Well-known songs where the B Dominant Ninth Chord — or this chord type — plays a prominent role:
- Purple Haze – Jimi Hendrix
- What's Going On – Marvin Gaye
- Superstition – Stevie Wonder
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| B | 493.883 Hz | 495.000 Hz | 490.548 Hz |
| D# | 311.127 Hz | 309.026 Hz | 313.951 Hz |
| F# | 369.994 Hz | 371.251 Hz | 367.911 Hz |
| A | 440.000 Hz | 440.000 Hz | 436.043 Hz |
| C# | 277.183 Hz | 278.437 Hz | 279.067 Hz |
Scales Containing the B Dominant Ninth Chord
These scales include the B Dominant Ninth Chord as a diatonic or characteristic chord: