How to Transpose for A Clarinet
The A clarinet sounds a minor third (3 semitones) lower than written pitch. When the A clarinet player reads a written C, the concert pitch that sounds is A — a minor third lower. The A clarinet is used primarily for orchestral works in flat keys, where its transposition gives the player a more comfortable written key signature than the Bb clarinet would provide.
The Transposition Rule
- Instrument Key
- A Clarinet
- Interval
- Minor 3rd (3 semitones)
- Direction
- Written is a Minor 3rd (3 semitones) above concert pitch
Concert Pitch to Written Pitch
To convert concert pitch to written pitch for A clarinet: go UP a minor third (3 semitones). Concert C major goes to written Eb major (3 flats). Concert Ab major goes to written C major (no accidentals). Concert Bb major goes to written Db major (5 flats). The written key always has 3 fewer flats (or 3 more sharps) than the concert key.
Written Pitch to Concert Pitch
To convert written pitch to concert pitch for A clarinet: go DOWN a minor third (3 semitones). Remove 3 sharps from the key signature (or add 3 flats). Written Eb major goes to concert C major. Written C major goes to concert Ab major. Written Db major goes to concert Bb major.
Worked Key Examples
Concert: C major — Written: Eb major (3 flats)
Concert C major (no accidentals). A clarinet player reads Eb major (3 flats: Bb, Eb, Ab). Written Eb sounds concert C, written F sounds concert D, written G sounds concert Eb. The 3-flat key signature is more challenging than Bb clarinet's 2-sharp D major for the same concert key.
Concert: Ab major — Written: C major (no accidentals)
Concert Ab major (4 flats). A clarinet player reads C major (no accidentals). This is the most comfortable key for A clarinet — no accidentals. Compare: Bb clarinet in the same concert key reads Bb major (2 flats). A clarinet gets the cleaner key signature, which is why composers score for A clarinet in flat-key works.
Concert: E major — Written: G major (1 sharp)
Concert E major (4 sharps). A clarinet player reads G major (1 sharp: F#). Concert E up a minor 3rd is G, so the written key is G major. Vs. Bb clarinet in E major: reads F# major (6 sharps). The A clarinet wins with the cleaner key signature for this sharp-key work.
Tips and Common Mistakes
Quick tip: The A clarinet gives the player a cleaner key signature than the Bb clarinet for flat-key orchestral works. In concert Ab major, the Bb clarinet reads Bb major (2 flats) while the A clarinet reads C major (no accidentals). Orchestral clarinetists carry both instruments and switch based on the key of each piece or movement. Mozart's Clarinet Concerto K. 622 is the most famous A clarinet work — it is always performed on A clarinet for its characteristic dark tone color and comfortable key signature.
Use the circle of fifths to visualize key signature relationships. Each step clockwise on the circle adds one sharp; each step counter-clockwise adds one flat. A Clarinet transposition moves 3 steps counter-clockwise (adds 3 flats) on the circle.
Instruments in This Group
Transpose with Precision — Get Tunable.
Tunable's chromatic tuner shows exact Hz values in real time. Use Tunable to verify your transposition by comparing written and concert pitch frequencies for all 1 A Clarinet.
