This specific fugue by Kirnberger demonstrates his strict adherence to traditional fugal construction as taught by his master, J.S. Bach. It is an excellent study in maintaining voice independence and structural clarity.
At Henle 4 this is an intermediate piece that expects secure technique and real attention to phrasing. The main demands: independent voices that must each sing on their own line; fine finger independence within the hand; and precise articulation — the difference between crisp and blurred is the piece.
Beyond that, expect chord voicing — bringing out one note inside a handful of others.
Focus on the clarity of voice leading and subject entries.
Comparable difficulty and character — good candidates for what to learn next.
A level or two down with the same spirit — ideal if this piece is still out of reach.
Where this piece's skills lead: slightly harder works making similar technical demands.
Lesser-known works by the same hand, at a comparable level.
Dreistimmige Fugue is rated Henle level 4 of 9 — intermediate repertoire, roughly ABRSM grades 5–6. In the RCM system it corresponds to about level 6.
You should be comfortable at Henle level 4 — meaning you can already play level 3–4 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 Dreistimmige Fugue lasts about 3 minutes.
Dreistimmige Fugue 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 Dreistimmige Fugue, EngK 31 by Johann Philipp Kirnberger, Allegro in D major by Johann Philipp Kirnberger, Courante in A-flat major, EngK 75 by Johann Philipp Kirnberger — see the full similar-pieces list on this page.