Few areas of the repertoire are as daunting to the casual listener as works for unaccompanied violin. Yes, everyone recognizes that Bach's six Sonatas and Partitas are masterworks, and many people thrill to the magnificence of the Chaconne from the second partita, especially if they hear it arranged for something other than solo violin. If you come across someone listening to these pieces regularly, chances are that he or she is, or has been, a string player.

The fact is that any substantial work for an unaccompanied string instrument is necessarily complex, implying the harmonies, counterpoint and rhythms that would be stated more explicitly in a more ordinary work. They will probably never have mass appeal.

Several composers since Bach have written for unaccompanied violin. The best-known is undoubtedly Paganini, whose Twenty-four Caprices make extravagent demands of a performer's virtuosity. They are very violinistic, but not quite as substantial as the Bach pieces, or those of a few other composers.

Perhaps the most familiar solo violin music of the twentieth century is Bartók's 1944 Sonata for solo violin, but the closest approach to Bach's method and feel are the six Sonatas for solo violin, op. 27 of Eugène Ysaÿe, written twenty years before Bartók's wonderful piece.

The appeal of these sonatas, once again, is mainly focused upon musicians and listeners with a good feeling for string instruments and all their subtleties. Yet other music lovers who take the trouble to become familiar with them will be amply rewarded. This is music that merits repeated hearings, each of which will reveal more to the attentive listener.

The best-known of the six is the Sonata no. 2 in A minor, which begins with a direct quotation from Bach's Partita in E, but soon wanders into less direct Bach-like digressions. The medieval sequence Dies irae appears repeatedly, as a sort of idée fixe. Movement titles like Obsession, Dance of the shades and The Furies suggest a bit of the atmosphere of the sonata, but words fall short in describing its actual sound.

There may be a violinist somewhere who plays this repertoire better than Ilya Kaler, but I can't imagine who. His surpassingly persuasive account of the A minor is but one of the fine offerings on this CD.

The most intimidating of the sonatas, with its somber and even tragic feeling and slow tempos, is probably the single-movement Third in D minor, the Ballade Sonata. Once again, Kaler delivers as lucid and engaging an account of the score as anyone could reasonably wish, making it more approachable than what one often hears..