If you want to play F7#5 on the mandolin, start with its notes: F, A, C#, D#. Its first mandolin voicing is the open position: G string at fret 2 (ring finger); D string at fret 1 (index finger); A string at fret 4 (little finger); E string at fret 1 (middle finger). This is a 7th sharp 5th chord, and the sections below take you from the notes table to real fingerings, common mistakes and the musical contexts where F7#5 sounds right.
What notes are in the F7#5 chord?
The F7#5 chord is a 7th sharp 5th chord, and its notes are fixed: F, A, C#, D#. Every voicing on every instrument uses these same notes, in some order and in some octave — change one of them and you are playing a different chord. The table below lists each note with its interval from the root F, so you can see the structure of F7#5 at a glance. On the mandolin, start with the first voicing above and listen for the notes F, A, C#, D# in F7#5.
| Note | Interval |
|---|---|
| F | Root |
| A | 3 |
| C# | #5 |
| D# | b7 |
The root is F, the note the chord is named after and the note your ear hears as home. Above it, the intervals in F7#5 are 3, #5, b7. Those intervals are the fingerprint of the 7th sharp 5th quality — any chord with the same interval pattern, on any root, is the same kind of chord. On the mandolin, the notes appear in the order the fingering dictates, but the set of notes never changes.
F7#5 sounds sharp and colourful, a dominant chord that refuses to sound ordinary. Listen for that character when you play it — if F7#5 does not sound that way, one of the notes is probably wrong, and the table above is the place to check. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
Comparing F7#5 with its closest relatives helps to fix it in your ear. In short, 7#5 against dominant 7th: F7#5 raises the 5th to C# where the plain dominant 7th keeps the perfect 5th C. The raised 5th adds lift and tension at the same time. Hearing the comparison matters more than reading it: play F7#5, then play the chord it is compared with above, and let your ear find the note that changed. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
How to play F7#5 on mandolin
On the mandolin, F7#5 has 3 voicings in the data below, and each one uses the same notes — F, A, C#, D# — in a different place on the neck. The first voicing below is the one to learn first, and the alternatives cover the rest of the neck. Finger numbers below use 1 for the index finger, 2 for the middle finger, 3 for the ring finger and 4 for the little finger, and x means the string is not played.
The open position puts F7#5 in open position: G string at fret 2 (ring finger); D string at fret 1 (index finger); A string at fret 4 (little finger); E string at fret 1 (middle finger). The stretch is the challenge: the fretted notes span from fret 1 to fret 4, so keep your thumb low behind the neck and let your fingers reach rather than squeezing the neck. Strum or pluck it slowly first and check that every note in F7#5 — F, A, C#, D# — sounds, with no buzz and no accidental open string.
For the movable voicing, F7#5 sits in around fret 3: G string at fret 6 (ring finger); D string at fret 3 (index finger); A string at fret 6 (little finger); E string at fret 5 (middle finger). The stretch is the challenge: the fretted notes span from fret 3 to fret 6, so keep your thumb low behind the neck and let your fingers reach rather than squeezing the neck. Strum or pluck it slowly first and check that every note in F7#5 — F, A, C#, D# — sounds, with no buzz and no accidental open string.
For the movable voicing, F7#5 sits in around fret 10: G string at fret 10 (index finger); D string at fret 11 (middle finger); A string open; E string at fret 11 (ring finger). This voicing is comfortable because the fretted notes sit close together, from fret 10 to fret 11, so your hand stays relaxed and every note can ring. Strum or pluck it slowly first and check that every note in F7#5 — F, A, C#, D# — sounds, with no buzz and no accidental open string.
Choosing between the voicings of F7#5 is a musical decision, not a right-or-wrong one. The open or low-position voicing rings the most and suits strumming, while a barre or movable voicing lets you slide F7#5 up the neck to any key without changing the shape. When you change chords, pick the voicing of F7#5 that sits closest to the chord before it — shorter moves between shapes mean faster, cleaner changes. Practise the change into F7#5 from the chord that comes before it in your song, not the chord on its own, because the move is the skill. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
A short practice routine for F7#5 on the mandolin: play the first voicing four times slowly, checking each note, then change to it from the chord a fourth above F and back, four times, at a slow tempo. Then play the second voicing the same way. If a note buzzes, stop and fix the finger placement rather than playing through the buzz — clean notes at a slow tempo become clean notes at full tempo, while buzzes practised fast become habits. Use the Mandolin Chord Finder to see the diagram for F7#5 while you practise, and the Chord Finder to compare it with the same chord on other instruments.
Common mistakes
These are the mistakes that most often make F7#5 sound wrong on the mandolin, and each one has a concrete fix. Work through them one at a time rather than trying to fix everything at once.
Missing one string of a course. Mandolin strings come in pairs, and F7#5 needs both strings of each course to sound. If one string of a pair is muted by a neighbouring finger, the chord sounds thin. Check each course separately by plucking it on its own. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
Playing a perfect 5th. If the 5th is C the chord is a plain dominant 7th. The sharpened 5th C# is the note that makes it altered. On the mandolin, start with the first voicing above and listen for the notes F, A, C#, D# in F7#5.
Confusing it with the augmented triad. The augmented triad has no 7th. F7#5 adds the flattened 7th D# to the augmented triad — that 7th is essential. On the mandolin, the open position voicing is the place to hear it in F7#5.
Using it as a tonic. F7#5 is an altered dominant. It wants to resolve to the tonic a fourth above its root. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
Where F7#5 is used
F7#5 is not a diatonic triad in any major or minor key, because it is an extended or altered chord, but its base triad belongs to the key of C major, the key of F major, the key of A# major. an altered dominant in jazz, where the sharpened 5th adds tension before a resolution. As a dominant-type chord it also points toward A# major, the key a perfect fourth above F, which is the tonic it most often resolves to. That is where F7#5 does its work: not as a home chord, but as a chord that creates movement and then resolves. On the mandolin, the open position voicing is the place to hear it in F7#5.
Because F7#5 is an extended or altered chord, it appears in progressions as a colour or a dominant rather than as a diatonic staple. Try it in place of the plain F triad in a progression you already know, and listen to how the extra notes change the feel — that substitution is the usual way extended chords enter real music. The Chord Progression Builder lets you try F7#5 in a progression in any key and hear how it connects to the chords around it. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
The same chord on other instruments is covered in F7#5 on guitar, F7#5 on piano, F7#5 on ukulele, and the scales that fit over it are the F major scale and the F minor pentatonic scale. Learning F7#5 on the mandolin and then checking it on another instrument is one of the best ways to fix the notes — F, A, C#, D# — in your memory, because the notes stay the same while everything else changes.
Practising F7#5
A short worked example makes F7#5 concrete. Play the four-chord progression A# – F – Gm – D# in A# major, the key F7#5 most often resolves toward: A# – F – Gm – D#. Play each chord for one bar at a slow tempo, and listen to how F7#5 sounds in that sequence — whether it feels like home, like a lift, or like a chord on its way somewhere else. Then play the same four chords in a different order, starting on F7#5 itself, and notice how its character changes when it opens the progression instead of sitting inside it. On the mandolin, the open position of F7#5 puts those notes under your fingers in the order the fingering lists them.
For a second exercise, play F7#5 and then the chord a fourth above F, back and forth, four times each. That move — a chord and the chord a fourth above it — is the most common resolution in Western music, and it is the move F7#5 is built for when it acts as a dominant. Finish by playing F7#5 on its own, slowly, and naming each note out loud as you play it: F, A, C#, D#. Naming the notes while you play them is what turns a shape into knowledge you can use in any key. Test yourself with the Practice Chord Quiz and keep time with the Metronome as the tempo rises. On the mandolin, the open position voicing is the place to hear it in F7#5.
Frequently asked questions
What notes are in F7#5?
F7#5 contains F, A, C#, D#: root F, major 3rd A, sharpened 5th C# and flattened 7th D#. The sharpened 5th is the note that makes it an altered dominant. On the mandolin, check the first voicing above for that note.
What is the difference between F7#5 and F7?
F7 has the perfect 5th C; F7#5 raises it to C#. F7#5 sounds tenser and more exotic, and it is used as an altered dominant in jazz. On the mandolin, check the first voicing above for that note.
Where is F7#5 used?
F7#5 is an altered V chord in jazz and minor-key progressions, used before a resolution to the tonic. It adds lift and tension to a dominant chord. On the mandolin, check the first voicing above for that note.
How do you play F7#5 on the mandolin?
The first voicing is the open position: frets 2–1–4–1, fingers 3–1–4–2, on the mandolin. That voicing uses the notes F, A, C#, D#, and it is the one to learn first. The page above lists more voicings for F7#5, so you can choose the shape nearest the chords around it.
Is F7#5 hard to play on the mandolin?
It depends on the voicing. The first voicing of F7#5 on the mandolin is the easiest starting point, and the movable voicings further up the neck are harder because they need a barre or a wider stretch. Practise the first voicing cleanly at a slow tempo before you try the others, and the harder shapes will come more easily.