Boosting a guitar's signal is easy, but it takes a sophisticated device to do it without adding distortion or affecting tone and response. One of the few pedals to actually achieve this is the hand-built Katana Clean Boost, from Keeley Electronics.
The secrets to the Katana's practically limitless headroom are audiophile-grade components and a specially designed I.C. known as a charge pump. This muscular circuit doubles the nine-volt input voltage to 18-volts before a set of FET transistors smoothly amplifies the sound.
The Class A Katana has a single side-mounted push-pull pot that lets users adjust the amount of boost with their foot. Pushing in the pot places the pedal in Pure Clean mode, where you get a healthy dose of clean boost. Pulling it out puts the Katana in High Gain mode, giving your tone a little tube grit just this side of overdriven.
Tested through a host of amps, the Katana was supremely transparent, offering everything from mild lift to radical boost while it maintained the precise nuances of my attack. It's like getting more from your amp without maxing out your gain. No wonder the Katana has found a place in the pedal boards of Z.Z. Top's Billy Gibbons and Anthrax's Dan Spitz, among many others.