Guitar players love the "warm" sound of amplifiers that use vacuum tubes. Players who intentionally overload them get sounds chip-driven amps can't match. Trouble is, vacuum tubes run hot, they wear out fast, they're more costly--and they're harder to find as the world moves to chips. So the hunt intensifies for solid-state amps that sound like tube amps.
Eric K. Pritchard, a custom-electronics designer in Berkeley Springs, W.Va., thinks he has the answer. Pritchard spent seven years with oscilloscopes, computers, and musicians trying to divine the essence of tubes. He says other efforts failed by not understanding the nonlinear behavior of vacuum tubes and the harmonic interactions between different stages of amplification. His company, Deja Vu Audio, has released its first product, the $2,000 Amp 11, which can be equipped with plug-in modules to sound like such great amps of the past as Jim Marshall's Plexi and Leo Fender's Black Faced Twin. Pritchard is winning believers. "I wanted to take the thing apart and find out where the tubes were hidden," says Paul C. Bechtoldt, a feature writer for Vintage Guitar magazine. Pritchard hopes to license the technology for all sorts of amplifiers, including recording gear and stereos.