For all their budding, precocious talent, Sleep's 1991 debut, Volume One, quickly betrays their still quite heavy debt to doom metal forefathers like Black Sabbath, Witchfinder, and Saint Vitus. Driven by Matt Pike and Justin Marler's lumbering mass of low-tuned guitar riffs, Al Cisneros' (still going as Luke here) serpentine bass and ragged screams, and drummer Chris Haikus' cyclopean kit pummeling, occasional highlights such as "The Suffering," "Nebuchadnezzar's Dream," and "The Wall of Yawn" prove less memorable than they are sensorially overwhelming. And yet, ironically, Sleep's rhythm guitars would never again be kept as under control, nor would their leads sound quite as refined as they do here (see the cleaner harmonies employed to good use on "Numb" and "Catatonic," for example). This was probably due to the onetime involvement of the significantly less stoned Marler, who would soon exchange the group for a monastery where he would study to become a monk. Fittingly enough, however, losing the versatility of a second guitarist was exactly what Sleep needed to focus their singular power into a crushing force, and the remaining trio would flourish immediately behind the sheer physicality of Pike's six-string style, as proven by 1993's superlative sophomore LP, Sleep's Holy Mountain.
AllMusic Review by Eduardo Rivadavia