Just two years after their debut, Cathedral pumped up the tempo and incorporated a slew of influences stretching beyond their solid, but somewhat limited, doom metal sound on Forest of Equilibrium. Shades of sludge à la Black Flag and The Melvins are most apparent, but the band reaches further beyond the low-and-slow realm to pull in influences from hard rock, heavy metal and progressive rock. Most importantly, the band's vibrant personality sheds its skin entirely and reveals its true colors, thanks in large part by an unhinged, dynamic vocal performance from Lee Dorrian. It's an exceptional combination that slightly edges out the band's initial groundbreaking efforts. Whereas several bands contributed to the sound developed in part by Cathedral on Forest of Equilibrium, there's never really been an album that sounds quite like The Ethereal Mirror, and it remains a multifaceted album with reverberations felt in music from the likes of Baroness, Pallbearer and a decent chunk of modern stoner metal.
We've covered a fair bit of ground with our Starter Kit series, where we select a handful of key records that highlight a niche musical style or penetrate the prolific status of a staple genre. Unfortunately, this format doesn't lend itself to covering proto-genres—microcosms of musical history comprised of a specific set of albums released in a fixed period of time. But these movements are crucial to the evolution of our favorite genres, particularly when it comes to the trajectory of sludge metal. What's become a multifaceted and often refined style was once a disparate lineage of bands from different genres who all applied the "sludge factor" in different measures. While you won't find a dedicated section for proto-sludge at your preferred music store, the following albums an artists laid the framework for the modern sludge landscape. So whether your sludge purveyors of choice come from the atmospheric, blackened or progressive sects of he genre, they're all indebted to the groundbreaking statements these albums made.