Al DiMeola's stage amplifier, like a lot of guitar amps, has two channels: one that produces a clean, crystalline signal, and another that emits an overdriven, fuzzy, "dirty" tone. At the Rams Head on Wednesday, the '70s fusion superstar occasionally played clean, but was drawn to the dirty channel as inevitably as an adolescent male home alone with the cable TV clicker.

Fuzzy guitar wasn't very popular in jazz in 1974, when DiMeola joined Chick Corea, Lenny White and Stanley Clarke in Return to Forever, the most revered combo in fusion history. DiMeola, only 19 at the time, brought an almost heavy-metal mind-set to the genre, showing off his inhumanly fast fingers in every solo, then bragging about his digital velocity in interviews with guitar magazines. DiMeola's brashness awed fans and fellow guitarists, but stuffier jazz critics ignored the precision of his playing, and harped that his speed-freaky style detracted from the music.

DiMeola put away his electric guitar by the end of the decade and went acoustic. Not because of the critics -- his acoustic playing in the intervening years is just as fleet -- but because he'd suffered hearing loss and severe tinnitis. DiMeola, backed by a Latin-centric quartet (two drummers, bass and keyboards), said his current tour marks his first electric shows since 1978.

Before turning to Corea's "Senor Mouse," he told the crowd how much fun it was to be plugged in again. And his fans, mostly middle-aged guitarophiles, were awed all over again when DiMeola showed, on that tune and throughout the 90-minute instrumental feast, that his fingers can still navigate a fretboard as quickly as ever.

While soloing on the golden oldie "Casino," DiMeola consulted sheet music on a stand. Given the fuzz-filled blizzard that ensued, the musical symbol for "play every note known to mankind NOW!" must have been on those pages. He picked up an acoustic Ovation guitar for "Misterio," but the licks remained as fast -- and the sounds as dirty -- as any Jimi Hendrix and his Stratocaster ever produced.

-- Dave McKenna

Guitarist Al DiMeola is playing his first electric concerts in 27 years.