Map it slowly
Find A on string 6 at fret 5. Play string 6, fret 5; string 6, fret 7; string 6, fret 9; string 5, fret 7; string 4, fret 6. Use a relaxed position and release pressure between repetitions. String 1 is high E.
Arpeggio · A△9 · Guitar
A△9 arpeggio on guitar
The A△9 arpeggio is A – C♯ – E – G♯ – B — chord tones 1 3 5 7 9. A△9 is a lush tonic chord in ballads; its sound is wide, luminous. Below, every A, C♯, E, G♯, B on the fretboard is marked, with the root in gold. Press play to hear a one-octave arpeggio, or tap any note.
Visualizer
A△9 on the fretboard.
Guitar · standard tuning
Piano
RootChord toneBeing played
Tempo100 bpm
Show
Sound
Play loops the arpeggio up and down one octave (switch Loop off for a single pass) in the position starting at fret 5. Tap any marked note to hear it. “Show” switches or combines the fretboard and keyboard; “Sound” picks the instrument you hear. Audio is synthesized in the browser.
Your next 10 minutes
Make A Major 9th part of your playing
Make a short phrase
Play A – C♯ – E – G♯ – B in quarter notes at 60 bpm. Repeat starting from C♯, wrapping back to A. Do not speed up until every attack is even.
Hear it in context
Alternate C♯ and G♯ above a sustained A. These are degree 3 and 7. End a four-bar phrase on either one instead of always returning to the root.
Listen for this: A△9 has the colour “wide, luminous”. Name the degrees as you play, so you can recognize the sound in another key rather than remembering only a shape.
Understand the sound
A△9: from a pattern to a musical choice
What gives A△9 its identity?
The ninth adds colour above a major-seventh foundation. Separate the upper voice from the bass and compare close and open spacing.
Here the third is C♯, and degree 7 is G♯. Play A in the bass and compare these voices individually before combining them.
Turn the arpeggio into a melody
Try C♯ – E – G♯ – A as quarter notes, then repeat the first note and omit the last. The second phrase uses the same harmony with a different shape.
Sound the strings separately before playing them together. If a note is muted, adjust the finger angle instead of squeezing harder.
Your guitar checkpoint
Start with A on string 6, fret 5. The next note C♯ is on string 6, fret 7. Name both notes aloud before playing, then find the same two pitches in another octave.
Before moving on, close the diagram and name the notes: A · C♯ · E · G♯ · B. Then play a two-bar phrase from memory and leave two bars of silence.
On piano
A△9 on the keyboard.
Reference
A△9 — chord tones & intervals.
| Chord tone | Note | Interval from A |
|---|---|---|
| 1 | A | unison (0 semitones) |
| 3 | C♯ | major 3rd (4 semitones) |
| 5 | E | perfect 5th (7 semitones) |
| 7 | G♯ | major 7th (11 semitones) |
| 9 | B | major 9th (14 semitones) |
Goes with: A Major (Ionian) (A B C♯ D E F♯ G♯). Voicings: see the four-note chord voicings in the chord library.
Take it to the bandstand.Practice Radio streams endless changes to play the A△9 arpeggio over through all twelve keys, with the chord and scale shown live — plus ear-training and call & response modes.
▶ Open Practice RadioCommon questions
A△9 arpeggio FAQ.
What notes are in a A△9 arpeggio?
A – C♯ – E – G♯ – B. As chord tones: 1 3 5 7 9. Played one after another instead of together, that is the arpeggio.
What is a A△9 chord used for?
A△9 is a lush tonic chord in ballads. Its character is wide, luminous.
Which scale goes with A△9?
A Major (A B C♯ D E F♯ G♯) — the arpeggio is the skeleton of that scale, so practise them together.
How do I practise the A△9 arpeggio on guitar?
Start on the root A on the low E string at fret 5 and play E-string fret 5, E-string fret 7, E-string fret 9, A-string fret 7, D-string fret 6, D-string fret 7. Then play it descending, then in eighth notes with a metronome, then use it in a short phrase over a suitable chord.
Keep going
Major 9th arpeggio in every other key.
Same arpeggio on piano · Major 9th hub · chord-scale theory.
Other arpeggios from A