Black Sabbath - Vol 4 (1972)

I was initiated into the cult of Black Sabbath via a borrowed copy of their self-titled debut LP, which my supercool buddy Elvin let me keep for ages. But it was 'Vol. 4', the band's unimaginatively titled fourth effort, that really meant something to me as I had saved hard to buy it and was hence determined to get my money's worth from every track.

To me, this is the BS album that captures the group not only at the peak of their powers (and prowess), but also at their most stylistically diverse. The songs may not be as easy to latch on to as their hits, but they display a striking sophistication that defied the much-maligned characteristics of the metal medium of the time.