Say you start a group called the Society for New Music, commission composer-stars-in-the-making and do it for thirty years straight, you might expect your scrapbooks to be quite interesting. What you might not realize is that your efforts now constitute a major segment of the backbone of contemporary American concert music and you have premiered a boatload of chamber works by composers who have gone on to distinguished careers. Such is the case with Syracuse’s Society for New Music founded by Neva Pilgrim, who opened their treasure chest of commissioned works from 1972 – 2002 and has put them together as the 5-CD set entitled “American Masters for the 21st Century.”