 Music scholar Edward Macan notes that the "post-psychedelic hard rock/heavy metal styles" that emerged had "a weaker connection to the hippie ethos" and "strongly emphasized the blues progression".Psychedelic rock, with its distorted guitar sound, extended solos, and adventurous compositions, had been an important bridge between blues-oriented rock and the later emergence of metal.Two former guitarists with the Yardbirds, Jeff Beck and Jimmy Page, moved on to form key acts in the new blues rock-heavy metal genre, The Jeff Beck Group and Led Zeppelin, respectively.