Like many artists who came of age in the early to mid-'60s, the Yardbirds went through some major creative changes in 1966. Leading up to this point was a series of singles, a couple of albums and a lineup switch that found Eric Clapton, the band's popular and idolized guitarist, replaced by another hotshot musician who helped guide the group into some new territories.

When Jeff Beck joined the Yardbirds in 1965, they had already racked up a Top 10 hit ("For Your Love") in both the U.S. and their native U.K. Their debut album, Five Live Yardbirds, didn't sell a ton of copies but it was a favorite among blues fans in England – where the band's live shows helped build their reputation with listeners who wanted something a little tougher than the pop tunes that mostly dominated the charts at the time.

But "For Your Love" was the last straw for Clapton, who despised the group's swing into pop material. Beck, on the other hand, embraced the possibilities, spinning the music -- still bluesy but decidedly rooted in the '60s, a leap Clapton was unwilling to take -- through a psychedelic filter that turned the corner for the Yardbirds.

Even though he stuck around for only a little more than a year and a half, Beck's influence on the group was huge. The singles they recorded together -- including another Top 10 hit on both sides of the Atlantic, "Heart Full of Soul," "Evil Hearted You" and "Shapes of Things" -- set the stage for their first real studio album in the U.K., Roger the Engineer, released in July 1966. (The album was slightly reworked and renamed Over Under Sideways Down in the States, where it was their third LP).

It's a monumental work of the era, as experimental as it is traditional in ways. (It's also the first Yardbirds album to include all original songs.) Beck, untied from the blues binds that Clapton adhered to, takes the Yardbirds into eye-opening, and mind-expanding, new worlds. Roger the Engineer helped set the template for the psychedelic-based hard rock that would emerge over the next couple of years. Beck's playing throughout, while not as precise as Clapton's, is bolder and in better service to the songs.

Its best tracks -- "Lost Woman," "Over Under Sideways Down" and "Hot House of Omagarashid" stand out, but the entire album folds together as a piece -- invite new colors into the Yardbirds base. But things started to fall apart for the band around this time. Bassist Paul Samwell-Smith quit before the album was even released, and Jimmy Page was brought in as a replacement. (The single "Happening Ten Years Time Ago" is one of the few Yardbirds songs to include both Beck and Page on guitar; John Paul Jones, who would join Page a few years later in Led Zeppelin, plays bass on the track, which is included on Roger the Engineer's CD reissue.)

While Roger the Engineer didn't crack the Top 10 (and its U.S. counterpart couldn't even make the Top 50), it ended up the Yardbirds' highest-charting LP in both the U.K. and U.S.

By October 1966, Beck was out of the band (his working relationship with the other members was tumultuous from the start), so Page led them through a few more sessions -- which were collected on the U.S.-only release Little Games in 1967 -- before they broke up in 1968. Some of the original members, without their celebrated trio of guitarists, reunited in 1992. Page went on to form the New Yardbirds with bassist Jones, singer Robert Plant and drummer John Bonham -- a group that later renamed itself Led Zeppelin. The seeds of their music, as well as much more from the period, were planted here.

1966's Best Rock Albums