This Kirnberger piece explores the harmonic color of A-flat major within a modest, structured classical framework. It is musically interesting for its exploration of key centers common in later classical development.
Focus on controlled finger pressure to achieve a singing tone in a non-standard key for the era.
Comparable difficulty and character — good candidates for what to learn next.
Allegro in A-flat major, EngK 50 is rated Henle level 3 of 9 — late beginner repertoire, roughly ABRSM grades 4–5. In the RCM system it corresponds to about level 5.
You should be comfortable at Henle level 3 — meaning you can already play level 2–3 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
A typical performance of Allegro in A-flat major, EngK 50 lasts about 2 minutes.
Allegro in A-flat major, EngK 50 is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.
Pieces at a comparable difficulty and character include Allegro fürs Clavier by Johann Philipp Kirnberger, 12 Variations on 'Ich schlief da träumte mir', EngK 68 by Johann Philipp Kirnberger, Ballet in B major, EngK 82 by Johann Philipp Kirnberger — see the full similar-pieces list on this page.