That the first psychedelic album might have come from a blues band was one thing. That one of the most influential blues albums of all time might have come from the same group, well, that was another.

That both things were wrapped up inside the Paul Butterfield Blues Band’s East-West, however, is undeniable — and, in the end, the album became a cornerstone for the group’s 2015 ascension into the Rock and Roll Hall of Fame.

Butterfield was joined on his sophomore record by guitarist Elvin Bishop, bassist Jerome Arnold, keyboardist Mark Naftalin, drummer Billy Davenport and lead guitarist Mike Bloomfield, who, like Butterfield, was at his peak. Each member brought his own interests into an increasingly collaborative structure.

"Pre-East-West, I was listening to a lot of [John] Coltrane, a lot of Ravi Shankar and guys that played modal music," Bloomfield once told WBEZ. "And the idea wasn’t to see how far you could go harmonically, but to see how far you could go melodically or modally. And that’s what I was doing in East-West, and I think that’s why a lot of guitar players liked it."

The band was photographed on the back cover of East-West making a mad dash, creating an indelible image -- both because of the mind-bending revelations found inside and also because of what we now know about the tragic Butterfield. Dead at just 44, the band leader and harmonica player's genius for stretching the limits of the typically staid blues genre was matched by his appetite for destruction. He moved fast, in both senses. Bloomfield, who also died young, followed Butterfield stride for stride.

East-West opened doors not just for the blues, but for all of rock. Butterfield stirred in raga and jazz, led the others on searing flights of fancy and played the harp with a fire and wit that drew favorable comparisons to legends like Sonny Boy Williamson II and Little Walter Jacobs.

"I remember sitting with Paul at a bar, probably the Bitter End, across Bleeker Street from the Cafe au Go-Go," Naftalin recalled in an interview years later. "And he told me that there was no guitarist in the country he'd rather have with him than Mike Bloomfield. I thought the band was screaming then. The effect of Paul and Mike mixing and matching was dizzying, and Mike and Elvin Bishop's guitars, when they were working together, made a beautiful section."

East-West arrived in August 1966 as a swift kick to the doors of convention, in particular with its Eastern influences and long-form jams. Both rock and blues were absorbed in the aftershocks for years. Its impact on Santana and the Grateful Dead, for starters, can't be overstated.

But like so much to do with Butterfield, the brilliant interplay with Bloomfield would prove to be short-lived. The former Bob Dylan sideman left after East-West, and the Paul Butterfield Blues Band retooled around Bishop, adding horns and taking on a more conventionally R&B tone. In this moment, however, we hear them doing things that had never been done, and doing them with a fearless abandon. East-West is history fashioned into something brand new.

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