It's pretty much a given that you can't really love rock and roll without at least having a fundamental appreciation of soul — the roots of both are inextricably entwined. Still, throughout the 1950s and well into the 1960s, the two traversed largely parallel paths. There were the rock charts and there were the R&B charts. Crossover hits were extremely rare on either side. Blame it on record label marketing, not any kind of veiled racism. Bean counters have never been renowned as visionaries.

Three nights at Bill Graham's Filmore West in March, 1971, made those bean counters open their eyes. San Francisco's famed venue played host to Aretha Franklin backed by King Curtis and the Kingpins for three straight shows, March 5-7. The lines between rock and soul would be forever blurred.

Two CDs from Rhino, appropriately titled Aretha Live at Filmore West and King Curtis Live at the Filmore West, document those events in digitally remastered recordings so crisp the listener is aurally transported to those concerts. This is Aretha at her apex, belting out gospel-infused soul in her inimitable style. This is King Curtis, playing sax and fronting his dream team version of the Kingpins, as if there were no tomorrow.

Aretha was already acknowledged as the "Queen of Soul," due in no small part to Jerry Wexler's tutelage since signing with Atlantic in 1966. King Curtis had a resume dating back to the fifties, and his sax stylings largely defined the instrument's role in in rock and roll. He was a musician's musician, though, and at that time, not a name generally associated with the rock scene. And while Aretha was an international star, most of the buzz surrounding her was generated from the R&B press.

So it was with some trepidation that Wexler brought Aretha and King to the Filmore West. By his own account, he wasn't sure how an audience accustomed to acts like the Grateful Dead and Jefferson Airplane would respond to what amounted to an all-out soul revue. He needn't have worried.

Aretha Live at Filmore West hits the ground running with a revved-up performance of "Respect" and Lady Soul's promise to the largely "hippie" audience that they will "enjoy this performance as much as any you have ever had the occasion to see." She makes good on that guarantee, and then some, with her take on "Love the One You're With," as different from the Steven Stills original as midnight is to dawn. Aretha's greatest strength lies in her ability to completely redefine source material, and nowhere is that more apparent than in her renditions of "Eleanor Rigby" and "Bridge Over Troubled Waters." Those two covers define the phrase, "it's not so much what you say as how you say it." And how she says it sends a shiver up the spine and a gut shot to the soul.