Whether New York is really losing its primacy as the undisputed American center of the arts is quite debatable. But it is becoming increasingly clear that the heart of the American orchestral organism is beating strongly 3,000 miles southwest of the Big Apple. The Los Angeles Philharmonic has achieved that rarest of confluences in recent years – a first-rate ensemble, a finely tuned promotional operation, a top-flight music director, and an outstanding and inviting concert hall. Perhaps more importantly, the LA Phil’s success may provide a blueprint for America’s more staid and stagnant orchestras (one of which resides in New York) to overhaul their own product.