Fans of the Seattle Chamber Music Society's Summer Festival have long been fascinated by the flow of new talent that mixes with the established regulars every July. This year, artistic director Toby Saks has a particularly fine crop of debutantes who are quickly emerging as heroes of the 2005 festival: violinist Jonathan Crow, pianists Alon Goldstein and Shai Wosner, violist Roberto Díaz and cellist Robert deMaine. To put it succinctly: They're spectacular.

Saks, a cellist, has an especially good track record with picking cello colleagues for the festival. DeMaine wowed opening-night audiences, and he went on to sail through a Boccherini Quintettino Wednesday evening. The Boccherini, an odd little work that almost amounts to a mini-concerto for cello with four other strings, also brought together violinists Carmit Zori and James Ehnes with Saks and violist Toby Appel. Zori and deMaine played perfectly judged little duets while the other players sat idle; it's an unusual piece.

Ehnes joined new violinist Crow in the pre-concert recital, a free event that now fills up well ahead of the 7 p.m. start time. No wonder, too, with these two super-hot fiddlers going head to head in duos of Bartók, Prokofiev and Wieniawski. There are lots of promising young violinists around, but they don't get much better than this pair.

The evening's surprise was the Gershwin "Lullaby" for string quartet, a graceful piece played by Ehnes, Appel, Zori and deMaine with the assurance of an established string quartet.

It was no surprise to hear Frank Kowalsky's expert traversal of the Poulenc Clarinet Sonata with pianist Goldstein. Kowalsky's limpid tone, broad stylistic range and tremendous control all contributed to a spirited account of this rather puckish sonata. Goldstein was perfectly attuned to the clarinetist.

One of the chamber repertoire's shiniest chestnuts, the Brahms Piano Quintet in F Minor, was the evening's big-event piece, assured of a passionate performance with Crow, Ida Levin, Díaz, Doane and Wosner. This was a true meeting of minds, with a conversational quality to the music. The playing was suitably fiery, but also refined; Wosner, who has a lot of big moments, was just this side of understatement, never dominating the ensemble as the pianist can. The cheers that erupted afterward were amply deserved.

Melinda Bargreen: mbargreen@seattletimes.com