Dweezil Zappa: Yeah. The thing about the gear is that Frank had a different perspective on how to use equipment than a lot of other guitar players. He had electronics built into his guitars that allowed him to equalize his guitar over the arrangement of the band. Basically, he had parametric equalizers in his guitars, and in most cases there were two of them in each.
You could choose the frequencies you wanted for clarity, and you could also choose frequencies to add more gain for smooth sustain, like what you hear on Zoot Allures when he hits a chord. It goes into that nice feedback. He was using recording equipment technology within his guitars.
He was used to working in a studio, mixing, and doing these things, so he incorporated that into his guitars. Very high class, hi-fi audio concepts were incorporated into his sound. He wasn’t using high gain amplifiers in the way that other people were; he actually had more gain from his guitar and would use the power amp section from his amps. There was more headroom and more dynamics, because the actual output from his guitar was 18db louder than a normal guitarmore