A major

A major (or the key of A) is a major scale based on A, with the pitches A, B, C, D, E, F, and G. Its key signature has three sharps. Its relative minor is F-sharp minor and its parallel minor is A minor. The key of A major is the only key where the Neapolitan sixth chord on (i.e. the flattened supertonic) requires both a flat and a natural accidental.
The A major scale is:
In the treble, alto, and bass clefs, the G in the key signature is placed higher than C. However, in the tenor clef, it would require a ledger line and so G is placed lower than C.
Scale Degree Chords
Tonic - A major
Supertonic - B minor
Mediant - C-sharp minor
Subdominant - D major
Dominant - E major
Submediant - F-sharp minor
Leading-tone - G-sharp diminished
History
Although not as rare in the symphonic literature as sharper keys (those containing more than three sharps), symphonies in A major are less common than in keys with fewer sharps such as D major or G major. Beethoven's Symphony No. 7, Bruckner's Symphony No. 6 and Mendelssohn's Symphony No. 4 comprise a nearly complete list of symphonies in this key in the Romantic era. Mozart's Clarinet Concerto and Clarinet Quintet are both in A major, along with his 23rd Piano Concerto, and generally Mozart was more likely to use clarinets in A major than in any other key besides E-flat major. Moreover, the climax part of Tchaikovsky's Violin Concerto is also in A major.
The key of A occurs frequently in chamber music and other music for strings, which favor sharp keys. Franz Schubert's Trout Quintet and Antonín Dvořák's Piano Quintet No. 2 are both in A major. Johannes Brahms, César Franck, and Gabriel Fauré wrote violin sonatas in A major. In connection to Beethoven's Kreutzer Sonata, Peter Cropper said that A major "is the fullest sounding key for the violin."
According to Christian Friedrich Daniel Schubart, A major is a key suitable for "declarations of innocent love, ... hope of seeing one's beloved again when parting; youthful cheerfulness and trust in God."
For orchestral works in A major, the timpani are typically set to A and E a fifth apart, rather than a fourth apart as for most other keys. Hector Berlioz complained about the custom of his day in which timpani tuned to A and E a fifth apart were notated C and G a fourth apart, a custom which survived as late as the music of Franz Berwald.
Notable compositions in A major
Antonio Vivaldi
Trio Sonata, Op. 1/9 RV 75
Violin Sonata, Op. 2/2 RV 31
concerto for two violins, Op. 3/5 RV 519
concerto for violin, Op. 4/5 RV 347
Violin Sonata, Op. 5/2 RV 30
concerto for violin, Op. 9/2 RV 345
concerto for violin, Op. 9/6 RV 348
concerto for violin, Op. 11/3 RV 336
Georg Philipp Telemann
Fantasia for flute solo, No. 1
Fantasia for violin solo, No. 5
Fantasia for viola da gamba solo, No. 8
Sonata for two flutes or two violins, No. 3
Johann Sebastian Bach
English Suite No. 1, BWV 806
Wolfgang Amadeus Mozart
Violin Concerto No. 5, K. 219
Symphony No. 29, K. 201
Symphony No. 21, K. 134
Violin Sonata No. 22, K. 305
Piano Sonata No. 11, K. 331
String Quartet No. 18, K. 464
Piano Concerto No. 23, K. 488
Là ci darem la mano, duettino form Don Giovanni, K. 527
Clarinet Quintet, K. 581
Clarinet Concerto, K. 622
Ludwig van Beethoven
Symphony No. 7, Op. 92
Piano Sonata No. 2, Op. 2/2
Piano Sonata No. 28, Op. 101
Violin Sonata No. 6, Op. 30/1
Violin Sonata No. 9, Op. 47
Cello Sonata No. 3, Op. 69
String Quartet No. 5, Op. 18/5
Franz Schubert
Trout Quintet
Piano Sonata, D 664
Piano Sonata No. 20, D. 959
Felix Mendelssohn
Symphony No. 4, Op. 90 ("Italian")
Organ Sonata, Op. 65, No. 3
Frédéric Chopin
Polonaise, Op. 40/1 ("Military")
Prelude, Op. 28/7
Franz Liszt
Piano Concerto No. 2, S.125
Johannes Brahms
Serenade No. 2, Op. 16
Violin Sonata No. 2, Op. 100 ("Thun")
Piano Quartet No. 2, Op. 26
César Franck
Violin Sonata
Anton Bruckner
Symphony No. 6
Émile Waldteufel
Les Patineurs waltz, Op. 183
Sergei Prokofiev
Piano Sonata No. 6, Op. 82
Dmitri Shostakovich
String Quartet No. 2, Op. 68
Symphony No. 15, Op. 141
See also
Major and minor
Chord (music)
Chord names and symbols (popular music)
References
External links
Musical keys
Major scales