He also recorded for several San Franciscan groups, playing on albums by Jefferson Airplane (with whom he performed at the Woodstock Festival), the New Riders of the Purple Sage and the Steve Miller Band.
Заметную роль Хопкинс сыграл в формировании «сан-францисского звучания», сыграв в альбомах Jefferson Airplane, New Riders of the Purple Sage и Steve Miller Band.