Were Pentangle a folk group, a folk-rock group, or something that resists classification? They could hardly be called a rock & roll act; they didn't use electric instruments often, and were built around two virtuoso guitarists, Bert Jansch and John Renbourn, who were already well-established on the folk circuit before the group formed. Yet their hunger for eclectic experimentation fit into the milieu of late-'60s progressive rock and psychedelia well, and much of their audience came from the rock and pop worlds, rather than the folk crowd. With Jacqui McShee on vocals and a rhythm section of Danny Thompson (bass) and Terry Cox (drums), the group mastered a breathtaking repertoire that encompassed traditional ballads, blues, jazz, pop, and reworkings of rock oldies, often blending different genres in the same piece. Their prodigious individual talents perhaps ensured a brief lifespan, but at their peak they melded their distinct and immense skills to egg each other on to heights they couldn't have achieved on their own, in the manner of great rock combos like the Beatles and Buffalo Springfield.