Appendix:
Main Differences in Teaching and Playing the Violin and Viola
There are obvious similarities between the two instruments and it seems like most of the exercises and etudes for violin can also be successfully transcribed for viola. The main technical differences appear in the area of sound production and bow movement. The larger size of the viola and thicker strings require somewhat different approach from the bow-arm towards producing a resonant, richly-textured sound. A slower movement of the arm, combined with more focused bow movement and more flexibility of right-hand fingers is preferable for viola. In this respect I actually find the approach to sound production somewhat similar to the cello technique: more concentration than speed and more attention to texture and color rather than brilliance.
Very often the lack of good tonal qualities in violin can be somewhat concealed by the technical brilliance of the conventional 19th-Century virtuoso repertoire. This is certainly not the case with viola. Despite numerous transcriptions and compositions of technically difficult pieces, the virtuosity is not the main characteristic quality of this instrument. In fact, in this respect, I consider the cello even more fitting the virtuoso image than the viola. Therefore, in my teaching and playing of the instrument I focus on what seems to be its quintessential quality – the reflectiveness of its unique timbre. This is especially important when we take into account the diapason of the viola, which reflects that of the human voice, minus the soprano (virtuoso!) range.
To summarize, while there are some differences between the violin and viola in the areas of left-hand finger action, vibrato, shifting, position and hold, bow-stroke preferences, etc., the most essential is the focus on a specific tone and texture that can be developed and produced only on a viola.