"I Can't Explain" was the song that -- in their native United Kingdom, at least -- launched the Who into stardom, reaching the Top Ten in early 1965 and giving a struggling young band the national exposure they needed to keep going. Much of "I Can't Explain" -- the famous intro and the verses, certainly -- is a basic three-chord romp, indebted to songs such as "Louie Louie" and the Kinks' early hits. That Kinks comparison is no coincidence, as at this point both groups were produced by Shel Talmy. Those opening, slashing chords -- thick and reverberant, though not as explosive and reverberant as the Who would shortly become -- embodied what came to be known, retrospectively if not at the time, as power chords and power pop. The verse alternates between Roger Daltrey's almost stream-of-consciousness declarations -- Pete Townshend would later claim the lyric was taking the part of a pilled-up mod, unable to coherently express himself -- and chirping, high, soulful backup harmonies with distant echoes of American groups like the Beach Boys and the Four Seasons. Those backing vocals, incidentally, are not by the Who, but by the group the Ivy League, roped into the session by Talmy as he felt the band's harmonies were not up to scratch. Indications that the Who had something more going for them than basic three-chord wonders were on hand in the brief bridge, with its brief venture into a minor key and an admission that the feeling the narrator was expressing might be love, not just a mixed-up blur of sensations. There were also the nifty guitar solos, again not as distorted and explosive as those the Who would soon employ, but with a manic intensity hinting at their eagerness to stretch and break boundaries. Instrumentally, however, the greatest flourishes were provided by a then-teenaged Keith Moon on drums, particularly at the point where the instruments and voices briefly stopped, jump-started back to life by rapid, furious drum rolls. Although "I Can't Explain" barely snuck inside the American Top 100, it would gain in popularity there as a Who standard when the group finally reached stateside stardom, becoming a staple of their live sets into the 21st century. The most famous and notorious cover of "I Can't Explain" is probably the one David Bowie put on Pin-Ups, his album of British mid-'60s rock covers, which slowed down the song to a ghoulishly slow tempo.