Op. 15 continues Mason's exploration of lyrical, evocative forms within the salon repertoire. It is harmonically richer than Op. 13 and demands a more sophisticated approach to tone color.
Students must develop a deep cantabile tone to sustain long phrases through changing harmonic textures.
Comparable difficulty and character — good candidates for what to learn next.
Ballade et barcarole (Op.15) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 7.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 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 Ballade et barcarole (Op.15) lasts about 5 minutes.
Ballade et barcarole (Op.15) 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 Ballade et barcarole by William Mason, Ballade No.1 by William Mason, Quejas, o la maja y el ruiseñor by Enrique Granados — see the full similar-pieces list on this page.