"Given that heavy metal didn’t completely take off until the 1970s – and the early part of the prior decade was dominated by pop, blues, R&B, surf music and rock ‘n’ roll – you’d be forgiven for thinking that the 1960s were lacking in significantly aggressive music. You’d be wrong, of course, but you’d be forgiven. In fact, it was around this time that artists such as Link Wray, Willie Johnson, Sister Rosetta Tharpe and The Kinks started pioneering and popularizing guitar distortion, power chords and/or unconventional means of modifying amplifiers to get gruffer sounds. During the second half of the 1960s, even rock artists who’re known for their lighter, brighter and poppier techniques ventured into some surprisingly hectic territories. As the songs discussed below demonstrate, many of the era’s top-tier acts released tracks that could’ve rivaled the riotousness of the burgeoning metal forefathers."