Peter Frampton is retiring, and once again I’m going through the process of losing close touch with a favorite artist and contributor to my musical history. “Frampton Comes Alive” was a seminal album on so many levels — a double album priced like a single LP (a big deal when you measured album purchases in allowance quanta), the album that converted me into a live music fan for life, the source of work and family vernacular that has survived 40 years, and the left bracket of my adulthood. It was, and is, equal parts the soundtrack to the throes of puberty and a trailer for the next forty years of concert experiences…