SignatureseriesCBCThe CBC Signature Series hosted by Paolo Pietropaolo forges on with A-flat major.

A little bit more on A-flat major from Wikipedia:

The A-flat major scale consists of the pitches A♭, B♭, C, D♭, E♭, F, and G. Its key signature has four flats (see below: Scales and keys).

Its relative minor is F minor, and its parallel minor is A-flat minor.

It was used quite often by Franz Schubert; twenty-four of Frédéric Chopin‘s piano pieces[quantify] are in A-flat major, more than any other key.

Beethoven chose A-flat major as the key of the slow movement for most of his C minor works, a practice which Anton Bruckner imitated in his first two C minor symphonies and also Antonín Dvořák in his only C minor symphony.

Since A-flat major was not often chosen as the main key for orchestral works of the 18th Century, passages or movements in the key often retained the timpani settings of the preceding movement. For example, Beethoven’s Symphony No. 5 in C minor has the timpani set to C and G for the first movement. With hand tuned timpani, there is no time to retune the timpani to A-flat and E-flat for the slow second movement in A-flat; accordingly, the timpani in this movement are reserved for the passages in C major. In Bruckner’s Symphony No. 1 in C minor, however, the timpani are retuned between the first movement in C minor and the following in A-flat major.

Charles-Marie Widor considered A-flat major to be the second best key for flute music.[1]

Sir Edward Elgar‘s Symphony No. 1 in A-flat major is probably the best-known symphony in that key in the standard orchestral repertoire.[citation needed] However, Arnold Bax‘s 7th Symphony is also in the same key.

A-flat major was the flattest major key to be used in the keyboard and piano sonatas of Domenico Scarlatti, Joseph Haydn and Ludwig van Beethoven, with each of them using the key for two sonatas: Scarlatti’s K. 127 and K. 130, Haydn’s Hob XVI 43 and 46, and Beethoven’s Op. 26 and Op. 110, while Franz Schubert used it for one piano sonata. It was also the flattest major key to be used for the preludes and fugues in Johann Sebastian Bach‘s Well-Tempered Klavier, as flatter major keys were notated as their enharmonic equivalents.

Felix Mendelssohn, Johann Nepomuk Hummel, John Field, and Friedrich Kalkbrenner each wrote one piano concerto in A-flat (Mendelssohn’s being for two pianos); they had the horns and trumpet tuned to E-flat. Max Bruch‘s Concerto for Two Pianos in A-flat minor has its last movement in A-flat major, which is the parallel major; this concerto plays with the contrast between the two keys.

Works for stringed instruments in this key include Antonin Dvorak‘s String Quartet No. 14 and Benjamin Godard‘s Violin Sonata No. 4.