The levels of difficulty of the piano music published by G. Henle Publishers:
| Level | Gradetable | Example |
| 1 | easy | Bach, Notebook for Anna Magdalena Bach, nos. 4 and 5 |
| 2 | Bach, Well-Tempered Clavier I, no. 1 Prelude C major | |
| 3 | Beethoven, Piano Sonatas op. 49,1 and 2 | |
| 4 | medium | Grieg, Lyric Pieces op. 12, no. 4 |
| 5 | Schumann, Fantasy Pieces op. 12, no. 1 | |
| 6 | Chopin, Nocturnes op. 27, nos. 1 and 2 | |
| 7 | difficult | Beethoven, Piano Sonata op. 10, no. 3 |
| 8 | Beethoven, Piano Sonata op. 81a | |
| 9 | Schumann, Toccata op. 7 |
Guide to the levels of difficulty
“I don't know what ‘difficult’ means. Either you can play or you can‘t” – this was the rather terse comment by the great violinist Nathan Milstein, on being asked about the unbelievable difficulty of Niccolo Paganini's Caprice no. 1.
The relativity of the evaluation of difficulty in music immediately becomes clear. Yet I gladly take up this great challenge, presented to me by G. Henle Publishers. For I am aware of how useful a guide like this can be, both from my own experience as well as that of many colleagues. In particular so as to be able to identify “appropriate” works. For example for music teachers, who teach at very different levels, from beginners to those preparing for music conservatories, but also for all those interested amateurs for whom this guide is intended.
After careful deliberation I have settled on nine levels of difficulty, which I have divided into three groups: 1–3 (easy), 4–6 (medium), 7–9 (difficult). A number of parameters have been considered when assessing the level of difficulty. I have not just looked at the number of fast or slow notes to be played, or the chord sequences; of central importance are also the complexity of the piece’s composition, its rhythmic complexities, the difficulty of reading the text for the first time, and last but not least, how easy or difficult it is to understand its musical structure. I have defined “piece” as being the musical unit of a sonata, or a single piece in a cycle, which is why Bach’s “Well-Tempered Clavier” Part I comprises a total of 48 levels of difficulty (each prelude and fugue is considered separately), Schumann’s Sonata in f sharp minor op.11 only has a single number. My assessment is measured by the ability to prepare a piece for performance.
Any evaluation of art or music will always be subjective, even if the aim was to be objective. Despite the fact that I have endeavoured to be as careful as possible, I am all too aware that the results of my work can be called into question, and am therefore grateful for any suggestions you might have.
Prof. Rolf Koenen © 2010