The classic Clean Boost, often seen on John Mayer's board.
Here's what Keeley Electronics say:
Our Katana Clean Boost is back and better than ever! Redesigned while going back to our roots.
We listened to what our players wanted and went back to our roots. The new Katana uses the original JFETs that made the original so special. We used the same component values from the original Katana, and updated the Boost mode to offer a more robust, clear sound, giving more clarity to bass notes when engaged. We updated the build with modern construction techniques to make this Katana the most dependable Clean Boost on the market, including an updated aluminium control knob, designed to be adjusted on the fly.
WANT A MIRROR IMAGE OF YOUR TONE, ONLY LOUDER? Roll the volume knob forward with your foot and you’ll be good to go! NEED EVEN MORE? The Katana Boost is also a fat, harmonically rich boost, just pull out on the volume knob and push the limits with overdriven tone! You can keep it on all the time to push your amp harder, or as an occasional boost to cut through the mix.
The Katana circuit is Robert Keeley’s first guitar effect design for Keeley Electronics. It was originally designed as part of the Time Machine Boost, but then became an independent product under the Keeley name after the release of the original Keeley Compressor.
Two modes, Pure Clean and High Gain
1. With the speed knob Pushed In, think of it as a volume control that goes to 20.
2. With the speed knob Pulled Out, it’s a cutting boost with a bit of gain. Not quite an overdrive, just overdriven tube grit and edge to your tone.
The Katana Clean Boost offers two modes. Pull the control knob for extra +30db Boost – It will make your signal sing!