A companion to 2016’s private country rock overview Cosmic American Music, this second volume goes way past Gram Parsons’ “country-rock plastic dry-fuck” and explores the twangy falsettos and commercial curiosity that sent the Eagles soaring. Though rooted in the west coast folk rock of the late-’60s, these new kids in town rendered a safe-for-the-suburbs sound bleached of the hippie era’s political strife.