4.5 stars – Indiana History Center; May 8. Last Saturday, music director Kirk Trevor ended his 22nd season with the Indianapolis Chamber Orchestra, a span that must be approaching some records, showing his mastery on the podium at its best. He attacked Mendelssohn's Symphony No. 4 in A, Op. 90 ("Italian") with as good a clarity and precision as I've heard anyone do it. Plus he generated all the excitement and charm latent in the composer's finest symphony, from its captivatingly tuneful opening Allegro vivace to the breath-taking Saltarello movement in A minor, a most unconventional key choice for a Finale. Its pounding mono-rhythm underlying the rapid string work, wonderfully phrased and articulated, the flutes carrying a fleet, harmonized tune . . . it all worked, according just accolades to its composer — and these performers. Preceding Trevor's grand final work, we had a return engagement of Canadian violinist Lara St. John joining the ICO strings in two views of The Four Seasons: one by Argentine tango master Astor Piazzolla, his "Autumn and Spring in Buenos Aires" and the universally popular version by Antonio Vivaldi — in this case his "Summer" and "Winter." Unlike what was shown in the program booklet, Trevor announced that the two composed versions, completing all four seasons, would be intermingled, such that Piazzolla's "Autumn in Buenos Aires" would be followed by Vivaldi's "Summer" and "Spring in Buenos Aires" would be followed by you-know-who's "Winter." While hearing hints of the tango throughout Piazzolla's contribution, it is unlikely to approach Vivaldi's in general interest. St. John and Trevor's strings gave both composers the spit and polish that foreshadowed the Mendelssohn.