BAROQUE ORCHESTRA AT AMBASSADOR AUDITORIUM

If anyone needs reminding, period instrument bands are no longer scratchy-sounding aggregations of semi-amateur eccentrics. Which, in the case of the Philharmonia Baroque Orchestra, may be no more than to say that it is a slick-sounding group of professional eccentrics.

Tuesday evening at Ambassador Auditorium, the Bay Area-based orchestra displayed virtually flawless ensemble and light, pleasant tone. Under the affable, peppy direction of Nicholas McGegan, the group has an assured, resourceful style that would sound polished by the standards of any age.

But three large suites of music, composed about the middle of the 18th Century for the orchestra of the Paris Opera, proved harder to appreciate than the verve and elegance with which the Philharmonians played them.

An extended group of dances from Rameau’s “Platee,” including two in encore, was the most consistently engaging. The pieces have a piquant, quirky character, often twitting dance conventions of the time, and Rameau produced some remarkably varied scoring from limited means.

Geminiani’s “Enchanted Forest” is also effectively scored, with even more restricted resources. But the interminable parade of mostly faceless little numbers thwarts serious concert concentration.

“Les Elements,” by Jean-Fery Rebel, begins with a striking depiction of chaos, a tremulous cluster of sound from which the elements gradually order themselves. Following that, though, Rebel’s music swiftly descends to genial banality and forgettable tunefulness.

However modest and fleeting the charms of this music might seem to the uninitiated, a taste for Philharmonia’s fluent, balanced playing is not hard to acquire. The arcana of French Baroque practice has been thoroughly assimilated, resulting in deftly pointed performances in which period style is an organic means, not a flaunted end.

McGegan bobbed and waved spiritedly in front of his 26 musicians, and offered a humorous verbal synopsis of “Platee.” The only disturbing feature of his interpretations was a tendency to clip final cadences extremely short, cutting “Les Elements” off in mid-trill, for example. His orchestra’s light sound did not produce much resonance in Ambassador, and that gave a very abrupt feeling to most of the endings.