The seven Concerti per Mandolini are diverse enough to disprove the frequently heard accusation that all Vivaldi concertos sound alike. Though they are cast in the same three-movement structure, each has its own character, from playful, ingratiating charm to ardor, high drama, and lamentatious intensity. The fast movements are stately and brilliant with scintillating running passages; the slow ones are songful, pleading, and melancholy. Though at times Vivaldi succumbs to his predilection for sequences, these pieces have an incredible variety of tonality, mood, and color, employing a large number of instruments in many arresting combinations; the final one requires 17 instruments. In addition to the solo mandolins, there are standard and unusual strings and winds, including such rarities as chalumeaux, theorbo, viole all'inglese, and violini in tromba marina. The performances, at lowered pitch, are splendid throughout: brilliant in the fast, virtuosic movements, perfect in intonation and balance, pure in sound, invariably expressive, often passionate. The players use vibrato sparingly and add elegant ornamentation and cadenzas. Biondi, director and concertmaster, has a wonderfully sweet tone and leads without dominating the group. One cavil: the musicians get louder on all ascending passages and softer on all descending ones, and they make a long pause before every final note. This approach may be stylistically "authentic," but it becomes an annoying mannerism through overuse and exaggeration