Mostly Mozart: an orchestra of festival quality

What began as a curiosity and a novelty -- a reasonably priced festival devoted to mostly one composer, held during the traditionally quiet summer months of a culturally frenetic city -- has become an institution that residents and visitors alike have come to rely on. This is the Mostly Mozart Festival's 19th summer at Lincoln Center. Its nightly sessions (except Sunday) offer a busy agenda of established and up-and-coming soloists, conductors, and chamber groups performing a wide variety of favorite and lesser-known music.

Gerard Schwarz became the festival's first music director last season, although he had been adviser since 1982. In his years of guiding this excellent but often errant ensemble, it has begun to fulfill its potential as an orchestra of festival quality.

But this is not all that is new and noteworthy here. July 10 marked the festival's first ``Live From Lincoln Center'' telecast, with a shrewdly chosen, engagingly executed program that included music of Mozart and Salieri. That program also boasted the festival's second United States premi`ere of a hitherto unknown Mozart symphony -- this time the A-minor (K. 16a) in three movements, discovered in Odense, Denmark, in 1982. This year will also see the release of Mr. Schwarz's first recording with the Mos tly Mozart Festival Orchestra.

The festival grew as a launching pad for many young American and lesser-known international performers -- the likes of Elly Ameling, who sang on the telecast, Alicia de Larrocha, Horacio Guti'errez, Garrick Ohlsson. These people either established their New York reputations or solidified their positions as meaningful artists under the auspices of Mostly Mozart, and they continue to be regulars.

The major concerts of the opening week were representative of what makes a Mostly Mozart evening pleasurable. Mr. Schwarz's programming of Salieri vs. Mozart was always engaging, be it the two composers' overtures written for the Viennese Emperor's dinner party for the visiting governors-general of the Netherlands, or two arias, sung by Miss Ameling. Even two standard works -- the 35th Symphony (``Haffner,'' in D, K. 385), and the mighty C-minor Piano Concerto, No. 24, K. 491. (Mr. Guti'errez the solois t) -- sounded fresh in this context. The second program, led by Raymond Leppard, offered Mozart, Handel, Purcell, Torelli, Fasch, and Haydn. The soloists were trumpeter Wynton Marsalis and soprano Erie Mills.

Mr. Schwarz's conducting gains yearly in finesse, nuance, and a deepening sense of how things should be and why. His reading of the ``Haffner'' Symphony was at once fleet, exciting, and heartfelt. His ability to accompany singers is gaining in nuanced assurance as well. Neither aria suited Miss Ameling, and yet Mr. Schwarz strove to make things smoother for her. With Mr. Guti'errez, too, the conductor listened, responded, and, even guided: The pianist often changed an interpretive direction from somethi ng merely smooth to something textured and interesting.

Mr. Leppard got fine things out of the orchestra as well, although his ideas of Mozart and Haydn are not as spry as they might be. He was at his best with the soloists, be it the amazing Mr. Marsalis, who seems able to spin out impossibly long, impossibly elegant phrases on one of the trickiest instruments around. Miss Mills brought her accustomed confidence and sparkle to her arias. However, she tended to wander from correct pitch in the second performance of the program.

The festival runs through Aug. 24 and includes many interesting programs and soloists. Two particular highlights will be the concert presentation of Mozart's early opera ``Mitridate, Re da Ponte'' on Aug. 15 and the festival debut of pianist Claudio Arrau on Aug. 23 and 24. 30{et