One could argue whether every track collected in this four-disc set is actually psychedelic or not, however one defines the term when it is applied to pop music, but everything here originally appeared at the close of the 1960s or the start of the 1970s, a time when pop music, and rock in particular, was expanding and playing with the notion of time, space, drugs, and a planet-wide pop culture.
All that aside, there are some classic decked-out sides here, psychedelic or not, like the Lovin' Spoonful's "Summer in the City," the Amboy Dukes' "Journey to the Center of the Mind," Santana's "Soul Sacrifice," Moby Grape's "Omaha," the Byrds' "Eight Miles High," and Argent's "Hold Your Head Up," among dozens of other slightly tilted hits from the era.