This is what we found on Wikipedia regarding the Go-Jo:

Pop rock (also typeset as pop/rock) is rock music with greater emphasis on professional songwriting and recording craft, and less emphasis on attitude than standard rock music. Originating in the late 1950s as an alternative to normal rock and roll, early pop rock was influenced by the beat, arrangements, and original style of rock and roll (and sometimes doo-wop). It is categorized both as a distinct music genre and as continuous categories of pop and rock. The detractors of pop rock often deride it as a slick, commercial product and less authentic than rock music.