Last week pianist Miles Graber performed in the Noontime Concert™ series to begin the set of three preview concerts for the Midsummer Mozart Festival. Today he returned with violinist Michelle Maruyama and cellist Robert Howard for an entirely different bill of fare. The only work on the program was Pyotr Tchaikovsky’s Opus 50, his only piano trio, in A minor. There are two ways to approach this music. All too often is provides an excuse for three virtuosi to come together (as, for example, Vladimir Horowitz, Isaac Stern, and Mstislav Rostropovich did for the 85th anniversary “Concert of the Century” at Carnegie Hall) and milk every page for opportunities to strut their stuff to the max. The alternative is to treat this composition as a serious piece of chamber music, composed with such ingenuity that it deserves to be ranked as one of the finest piano trios of the nineteenth century. That superlative might even extend to all of nineteenth-century chamber music, if not the full canon of the chamber music repertoire. Graber, Maruyama, and Howard were clearly committed to this latter strategy; and anyone who had doubted that Tchaikovsky had significant merits could not help but change his/her mind by the time this performance reached its final measures…