In Bartok’s Piano Concerto No. 2, sandwiched between the Classical Haydn and the Romantic Schubert, in the Israel Philharmonic Orchestra’s recent concert, the composer made the piano a percussion instrument.Soloist Yefim Bronfman, rising to the challenge, played the fast movements with a powerful percussive touch that sounded like elemental forces let loose. Despite brilliant, breathtaking virtuosity, he also produced an enchanting soft touch in the slow movements, conveying their lyric mood with refined sensitivity. In a Scarlatti sonata, as an encore, he then proceeded to demonstrate that besides being an enormously impressive virtuoso, he is also a master of utmost delicacy.Conductor Zubin Mehta performed an accurate, unsmiling, standard rendition of Haydn’s Miracle Symphony and Schubert’s Symphony No. 9. If in these masterworks he had displayed the same degree of enthusiasm, contagious excitement, flexibility and Viennese esprit as in Johann Strauss’s Fledermaus Overture, played as an encore, this concert would have been a pure pleasure.