Construction
| Note | Interval | Degree |
|---|---|---|
| F♯ | Root | 1 |
| B | Perfect 4th | 4 |
| C♯ | Perfect 5th | 5 |
Fingering
| Note | Key color | Right hand | Left hand |
|---|---|---|---|
| F♯ | black | thumb (1) | little finger (5) |
| B | white | middle finger (3) | middle finger (3) |
| C♯ | black | little finger (5) | thumb (1) |
Right hand: thumb (1) on F♯, middle finger (3) on B, little finger (5) on C♯.
Left hand: little finger (5) on F♯, middle finger (3) on B, thumb (1) on C♯.
F♯ Suspended 4th Inversions
- Root positionF♯ – B – C♯
- 1st inversion (F♯sus4/B)B – C♯ – F♯
- 2nd inversion (F♯sus4/C♯)C♯ – F♯ – B
Key Signature
A Suspended 4th chord is built from symmetrical or ambiguous intervals, so it doesn't belong to a single key and has no key signature of its own.
Chords in the Key of F♯ Major
These are the triads built on each degree of F♯ Major:
Scales That Include the F♯ Suspended 4th
Same Notes, Other Names
The notes F♯ – B – C♯ aren’t exclusive to this chord. Depending on which note is the bass and how the chord functions, the same pitches also spell:
F♯ Suspended 4th : Frequently Asked Questions
What is the F♯ Suspended 4th chord on piano?
What is the F# piano chord?
What notes are in the F# Suspended 4th chord?
How does F# Suspended 4th differ from F#sus2?
What does "sus4" resolve to?
How is F# Suspended 4th used in music?
What songs use suspended 4th chords?
Can I use F# Suspended 4th before F# Major?
F♯ Suspended 4th in detail
Exact
Every pitch class is present and nothing outside the chord is added.
| Type | Notes | Semitones | Span | Omissions and additions | Set relation | Fit |
|---|---|---|---|---|---|---|
| Close, root position | F♯3 B3 C♯4 | 7 | 96 mm | none | identical | |
| Close, first inversion | B3 C♯4 F♯4 | 7 | 96 mm | none | identical | |
| Close, second inversion | C♯4 F♯4 B4 | 10 | 138 mm | none | identical | |
| Open, fifth on top | F♯2 C♯3 B3 | 17 | 234 mm | none | identical |
Reduced
A subset of the pitch classes: the identity is incomplete rather than altered.
| Type | Notes | Semitones | Span | Omissions and additions | Set relation | Fit |
|---|---|---|---|---|---|---|
| Root and third only | F♯3 B3 | 5 | 69 mm | omits C♯ | subset |
Spans are measured centre to centre at a 165 mm octave (standard keyboard geometry).
| Position | Bass note | Notes in order | Figured bass | Semitones | Span |
|---|---|---|---|---|---|
| Root position | F♯ | F♯3, B3, C♯4 | 5/3 | 7 | 96 mm |
| First inversion: F♯sus4/B | B | B3, C♯4, F♯4 | 6/3 | 7 | 96 mm |
| Second inversion: F♯sus4/C♯ | C♯ | C♯4, F♯4, B4 | 6/4 | 10 | 138 mm |
One position per chord tone in the bass. Spans are for close position: voiced inversions appear under Voicings.
| Progression | Key | Role | Sequence | Voice leading |
|---|
Root motion, common tones and voice displacement are computed from pitch class sets. Roman numerals follow common practice functional harmony.
Change one note
Chords a single note away, and what moving that note does.
| Chord | Change | Formula | Common tones |
|---|---|---|---|
| F♯7sus4 | adds E | 1 4 5 ♭7 | 3 |
| F♯ | B becomes A♯ | 1 3 5 | 2 |
| F♯m | B becomes A | 1 ♭3 5 | 2 |
| F♯sus2 | B becomes G♯ | 1 2 5 | 2 |
| F♯maj7 | B becomes A♯, E♯ | 1 3 5 7 | 2 |
| F♯7 | B becomes A♯, E | 1 3 5 ♭7 | 2 |
| F♯m7 | B becomes A, E | 1 ♭3 5 ♭7 | 2 |
| F♯mMaj7 | B becomes A, E♯ | 1 ♭3 5 7 | 2 |
| F♯6 | B becomes A♯, D♯ | 1 3 5 6 | 2 |
| F♯m6 | B becomes A, D♯ | 1 ♭3 5 6 | 2 |
| F♯add9 | B becomes A♯, G♯ | 1 3 5 9 | 2 |
| F♯dim | B, C♯ becomes A, C | 1 ♭3 ♭5 | 1 |
Frequencies
| Note | MIDI | Frequency |
|---|---|---|
| F♯3 | 54 | 185.00 Hz |
| B3 | 59 | 246.94 Hz |
| C♯4 | 61 | 277.18 Hz |
Reference pitch A440, 12-TET, close root position.
Set theory: prime form, Forte number, interval vector
- Absolute pitch class set
- {6, 11, 1}
- Normal order
- [11, 1, 6]
- Prime form
- (027)
- Forte number
- 3-9
- Interval vector
- <010020>
| Pair | Interval | Semitones | Interval class |
|---|---|---|---|
| F♯ to B | Perfect fourth | 5 | 5 |
| F♯ to C♯ | Perfect fifth | 7 | 5 |
| B to C♯ | Major second | 2 | 2 |
Where these facts come from
Every value on this page is derived from the note formula for a suspended 4th applied to the root F♯, using standard music theory. Nothing here is hand-entered per chord, so the notes, intervals, inversions and frequencies cannot drift out of agreement with each other. Pitches assume 12-TET at A440.