In his acclaimed book Elevator Music: A Surreal History of Muzak, Easy-Listening, and Other Moodsong, author Joseph Lanza explored the forbidden beauty and social importance of an otherwise shunned musical category. Now, in Easy-Listening Acid Trip, he pushes the boundaries further by taking his subject into altered states, showing how psychedelic pop (as opposed to the ear-grinding jams of "acid rock") offered other worlds and strange...