With special guests

8 p.m. March 22

Ingram Hall, Blair School of Music, 2400 Blakemore Ave.

For ticket information, call 322-7651

For some years, the Blair String Quartet were the premier classical ensemble in Music City. They were an exhilarating reminder that, though recorded music is an enormous blessing, live acoustic sound in a good space can move listeners as no other sound can. Their programming core was mainstream—from Haydn and Mozart through Beethoven to Bartók and Shostakovich. But they also played compositions by living composers, including their colleague Michael Kurek.

That foursome had been together for more than a decade. Each was an accomplished soloist; but they had become a foursome that played like a soloist, and the music they made often took the breath away. This particular avatar of the quartet died a couple years ago when cellist Grace Mihi Bahng left the group.

The effects of that departure were not seismic, but they were audible. A new cellist, Felix Wang, was named right away; he was a superb performer, and from his first day in the chair (in 1999), the new quartet played very well. But they did not play with the concise and confident unanimity that had been in their DNA for at least half a dozen seasons. More than a season of adjustment and accommodation ensued before the new foursome became a precise team. But the BSQ have come back.

Their confidence shows in the program chosen for their performance this weekend. On one hand, that program will allow the quartet to showcase their own special resonance in a middle-period Beethoven string quartet. On the other, it dares the BSQ to blend their music with sounds issuing from some special guests.

Friday's concert in the new Ingram Hall will present, in addition to the Beethoven quartet, a string sextet by Johannes Brahms and Felix Mendelssohn's only string octet. In substance, this entire program is mainstream stuff—all published between 1814 and 1867. But it's very special stuff too, and each selection makes its own exacting demands.

The Beethoven offers the BSQ ample opportunity to show what they can do on their own. Beethoven wrote string quartets in each of the three conventional periods of his career. In 1800 he published six early ones that carry his thumbprint, but taste a lot like Haydn and Mozart. Then, in an experimental middle period, he published five more: three in 1806, one in 1809 and another in 1814. (The three from 1806, the "Rasumovsky" quartets, remain for many listeners his most attractive in the genre—though the first quartet to play them thought they were "crazy music.") After the last middle-period quartet in 1814, Beethoven would wait more than a decade before producing the half-dozen jagged and seismic late quartets that godfathered Bela Bartók.

The 1814 quartet ("Serioso"), chosen to lead off this program, embodies the expanding and transfiguring of the composer's musical inheritance into iconic Promethean musical genius. The current BSQ—Christian Teal, Cornelia Heard, John Kochanowski and Felix Wang—will raise that body from the score in this performance.

Then, joined by two former members—Kathryn Plummer, the BSQ violist from 1974 to 1987, and Bahng, the cellist from 1984 to 1999—they will play the second of two string sextets by Johannes Brahms. A scrupulously erudite musical genius, Brahms creatively metabolized Renaissance and Baroque polyphony with folk and dance idioms and the language of mid- and late 19th-century art music to bring forth richly textured, elegantly disciplined works of intense passion. He wrote masterworks in most musical genres, from symphonies to sonatas. But none are more masterly than the 24 complete chamber works he produced over some 40 years. This sextet is one of the finest exemplars.

Brahms' musical productions invite comparison with Michelangelo sculptures: Both artists create epic embodiments of enormous emotional force in highly polished architectonic forms. This second sextet was completed in 1866, when Brahms was 33. Music historian Donald Jay Grout calls it "serene"; Brahms himself labeled it heiter (jovial, jolly), which is maybe a stretch. But it is certainly full of sanity and gusto—and of fecund inventiveness.

Music historian Piero Weiss observes that in chamber music, "the difference between four and six is greater than two." The four voices of a quartet are essential, he says. Adding another one or two or more sets some voices free to enrich and embellish. Brahms takes advantage of that freedom. This sextet opens with characteristic symmetry: The main theme efficiently outlines keys (E-flat and B) located a major third on either side of the home key (G Major). This symmetrical first movement has a limpid, open, even ethereal texture. The second movement, a scherzo, wavers between melancholy and playfulness in a distinctively Brahmsian way. The third is a set of slow and ingenious variations ending in solace and repose. The finale, Weiss says, is "a return to reality after a magical dream." It's anchored by a vigorous fugue that is introduced, dissolves and then is reintroduced at the end, at dizzying speed, bringing the work to a "rousing and—yes—jovial conclusion."

Either Beethoven or Brahms alone would be a tough act to follow. Both together are intimidating indeed. But the Mendelssohn octet is up to the challenge—even though it was written when the composer was only 16. By the time a series of strokes killed Mendelssohn before he was 40, he had stood at the forefront of German music for nearly 20 years—as pianist, organist, conductor and composer. A Mozartean kind of prodigy, he produced in this octet a masterpiece that even Mozart did not match at that young age.

And this work is its own thing—a compositional tour de force. Mendelssohn brilliantly exploits the possibilities for instrumental combinations, ranging from minimalist unison textures in the scherzo to an intricately contrapuntal eight-voice fugato finale. Perhaps the work's essential trait is its artesian exuberance, culminating in the hell-for-leather finale that includes a quotation from Handel's "Hallelujah" chorus. Rightly done, it will bring a house to its feet.

In choosing this program, the Blair Quartet and its special guests raise the bar quite high for themselves. Individually, they must play very exacting music very exactly. Equally crucial, they must play it together. For the octet, the six players named above will be joined by Carolyn Huebl, a new adjunct violin professor at Blair, and by Joseph Silverstein, violinist for the Lincoln Center Chamber Music Society. These guys are good. This particular pudding remains to be proved. But delicious aromas are wafting out of the kitchen.