Roberto Diaz, master of the viola

Maria Thompson Corley echoed my own sentiments recently when she complained about musicians who move too much. Performers who hop around a lot may impress viewers who confuse motion with emotion, but they often put most of their feelings into their body language and neglect to include it in their music.

The visual aspect of a live concert is one of its appeals, but it needn't involve torrents of emoting. One pleasure of chamber music is the sight of skilled artists creating great works of art right before your eyes. Such a process is so interesting in itself that it needs no embellishments.

Roberto Diaz provided a good example of an appropriate visual display at his recital for the Philadelphia Chamber Music Society. Diaz made no effort to woo the audience with his movements, but several times his demeanor underlined the music with an appropriate visual backup.

In the opening item, I was struck by the ease Diaz displayed as he sat on a piano stool playing the lead role in a Paganini piece that's primarily a viola solo accompanied by guitar, violin and cello.

Eyes focused on hands

Later, in the slow movement of Hindemith's Sonata for Solo Viola, I was just as impressed by the way Diaz stood on the stage with his eyes focused on his hands, utterly absorbed in his instrument. Both his ease and his intensity spoke volumes about his music and the nature of his involvement with it.

The natural interactions of the players add something, too. Allen Krantz didn't stand up or strike a pose when Paganini's score presented the guitarist with a solo, but my mental spotlight automatically illuminated his section of the stage.

Diaz had invited two Curtis students to join him in the Paganini. In a section that included a dialogue between the viola and the violin, Rebecca Anderson responded to her senior partner— who is also the head of her school— with a verve that matched the messages she was receiving from the other side of the platform. It wasn't hard to imagine what it might be like to be 19 years old and sharing the stage with a musician of Diaz's stature.

The violists joke

Violists, according to the standard joke, are supposed to be musicians who couldn't make the grade as violinists. Roberto Diaz is a virtuoso who can silence any violinist who dares to express that nasty canard. He creates a powerful tone, with all the viola's dark beauty, and he can produce flashy passages that are just as exciting as anything you'll hear on the smaller, higher-pitched instrument played by his upscale colleagues.

All three pieces Diaz chose for his recital were winners. Paganini was a first-class guitarist, in addition to his prowess on the violin, and you can be confident any Paganini piece that features the guitar will be a delight.

Hindemith's violin sonata is a good example of the sonatas Hindemith wrote for instruments that could use a few additions to their solo literature. Hindemith put some of his best work into those pieces. The sonata for unaccompanied viola fully deserves its standing in the viola repertoire.

The Shostakovich was the last piece that composer wrote. Diaz said he has discussed it with the violist for whom it was originally written in 1975 (presumably Fyodor Druzhinin), and his performance reflected the understanding he had acquired during a three-hour conversation that examined the piece almost note by note.