If you haven’t had your Mozart fix in a few months, the Midsummer Mozart Festival is here to help you out. The impressive lineup of the first concert begins with the overture to Idomeneo, a great piece, but not so often played. The incredibly musical Jon Nakamatsu, who can be amazingly delicate, is the soloist in the Piano Concerto No. 26 in D Major (“Coronation”) and soprano Christina Major sings two famous concert arias. The orchestra returns for the “Linz” Symphony, No. 36 (and here’s hoping that Maestro George Cleve takes the first movement exposition repeat). It’s the mature composer at his world-beating best.