For many people, Sasha and John Digweed, who appear Friday, May 17, at the Fillmore Auditorium, define the clubbing experience. As evidenced by their live performances, both are masters of taking classic house records and weaving them into a nearly perfect web of more progressive grooves. Newly free from a residency at New York City's now-defunct Twilo, the two friends -- who are consistently rated among the top five DJs in the world by sources such as DJ Magazine -- have embarked on their first-ever arena-sized multi-city headlining tour. "Delta Heavy," produced by Immortal Records honcho Kevin Lyman, boasts a massive Phazon sound system guaranteed to shake the floor with clean, booty-shakin' bass. Sasha and Digweed have also brought along Imaginary Forces, the company behind the opening-credit sequence in the film Se7en, to do visuals for the tour. Fancy sounds and lighting are nice, but the faithful would come and see the pair if they were spinning in a dingy basement with a single forty-watt bulb and a boombox. Even the most casual clubber should seize the rare opportunity to see Sasha and Digweed together.