When connecting an external effects processor/multi-effect/pedalboard (GT-1000/GT-1000CORE/GX-100/ME-90 etc.) to your KATANA MkII, the pedalboard output signal will input directly into the POWER AMP INPUT and the Power amp of your amplifier, thus bypassing your amplifier's Preamp (panel controls). This is useful if you want to use a sound shaped by an external preamp or multi-FX unit that is equipped with amp simulators.
The main BTS/BOSS Tone Studio MkII window is disengaged when the POWER AMP IN socket is in use, and connection is established; you'll have more limited parameter control adjustments in the SYSTEM > POWER AMP IN SETTING menu, for the POWER AMP, these controls are useful if you are experiencing some muddy sound or odd frequencies for your output sound. Some EQ options are available for adjustment to improve the pairing of your multi-effect and the KATANA MkII amp output sound.
For this, you will need a KATANA MkII with a POWER AMP IN socket and this will need to have the latest firmware, USB driver installed, and latest BTS for KATANA MkII software editor installed, USB 2.0 A to B printer data cable, and all connected/synced together.
You can download your relevant operating system drivers, the firmware update, USB drivers, and BTS for KATANA MkII software editor using the following link.
BOSS KATANA MKII | Guitar Amplifier
Once you are set up and connected with your KATANA MkII amp with the BTS for KATANA MkII, open up the SYSTEM tab at the top of the main window.
From here, select POWER AMP IN SETTING. You'll see the below window.
To fine tune your POWER AMP IN EQ, adjust the dials appropriately.
Here's a brief explanation of what each parameter does:
HPF TYPE
This is the SLOPE of your high pass filter that will determine the drop in dB per octave of the filter. It also moderates how aggressive the filter is. The higher the dB drop, the more aggressively cut your lower frequencies are. Having this set to FLAT means there are no cuts in the audio.
HPF FREQ
The high pass filter frequency sets which point the equalizer allows frequencies to pass through. For example, if this is set to 50Hz, frequencies above this point are passed through, whereas anything below is attenuated (or not passed through). You may also see this described as a cut-off frequency.
LEVEL
This controls the overall level of your POWER AMP IN EQ.