Jun Yamamoto’s three-voice canon is a study in tonal counterpoint with a contemporary sensibility. It is distinguished by the clarity of its three-part interplay and accessible melodic writing.
Balancing the three voices so that the canonic subject is always audible is the main technical task.
Comparable difficulty and character — good candidates for what to learn next.
Canon 3-voice in A major 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 Canon 3-voice in A major lasts about 3 minutes.
Canon 3-voice in A major 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 Canon 4-voice ascending 6th in B-flat minor by Jun Yamamoto, Canon 4-voice ascending 6th b moll by Jun Yamamoto, Canon 4-voice descending 6th in C minor by Jun Yamamoto — see the full similar-pieces list on this page.