This week Mariss Jansons leaves his post as music director of the Pittsburgh Symphony. “Jansons inherited an ensemble of first-rate musicians. And with that beaming smile and charming personality, he navigated them to warmer artistic waters. If they were choppy at times, it’s clear Pittsburgh and its orchestra ultimately benefited from him as captain, and he with them. The city that repaired his heart with a defibrillator and warmed it with a cordial writing campaign received in return the kind of passionate performances that result in the loftiest of musical standards.”