Great advice from @GrytPipe
I would also spend a little time getting to know your basic level controls on the amp too, if you haven’t. By “basic level controls” I mean the “gain”, “volume”, and “master” controls (as well as the power control settings).
Amps like the Katana are extremely flexible, but that also means there’s a lot of knobs to play with, and it’s easy to end up tweaking lots of stuff and not really understanding what’s happening. And,even when it comes to something as simple as “how loud is this thing” there’s a lot of controls and options to balance.
I would start by setting the Katana to a single channel such as “Crunch”, turn off all effects, set the EQ to 12’O’Clock and then play with the gain, volume and master controls to get an understanding of what they do.
Here’s a rough explanation:
Pretty much all audio amps actually have two amp circuits in them: a pre-amp and a power amp. The power-amp provides the electrical power to drive the mechanical speaker, and is primarily responsible for making the overall tone louder or quieter.
The pre-amp is responsible for making the tiny electrical input signal higher, high enough for the power-amp to deal with.
In a guitar amp, the pre-amp is also where most of the distinctive amp tone comes from. It’s here that overdrive is used to shape the sound by over-driving the pre-amp circuits, and guitar pre-amps are designed so that the input level can be turned up in order to get over-drive.
The control which does this is the “gain” control on the Katana. This is the only one of the basic level knobs on the Katana which should cause the tone to change substantially. All of the other level knobs are ways to make the overall sound louder or quieter.
Note you also have the (poorly named IMO) “volume” pot on your guitar which impacts the level going into the pre-amp, and is kind of like an additional “gain” control that you can use as well as, or instead of, the gain control on the amp.
The primary motivation of the “gain” control is to impact how hard the pre-amp is driven, in order to create overdriven tones. Yes, it will change the absolute volume level as well, because that’s how “gain” works. But that is not its primary function, and it’s a mistake to use the gain control like this. The gain control should really be used only for tone shaping.
As I said, everything else happens after the pre-amp, and is only concerned with the volume coming from the speaker, and not changing the tone.
So use the “gain” knob to get the tone you want, and use the other controls to get the volume you want.
Ideally you want to be able to set the master volume control and power control to a level you like, and then use the pre-amp “volume” control to adjust the level of individual patches so that they are roughly the same. You don’t want to be messing with the master volume control every time you change to a different setting.
So in everyday use, you should normally only be messing with the gain control for tone shaping, and the volume control to offset the volume changes caused by changes to the gain control.
Of course, as soon as you stick pedals in front of the amp, this complicates things further, as you then, potentially, have the ability to boost or cut the signal on each pedal.
My advice here for “non-gain” pedals, like compressors, delays, etc.: get what you want from the amp with the pedals turned off/bypassed and treat that as your baseline tone.
Then you can mess around with the pedal controls. If doing something on the pedal then makes the amp too loud, then turn down the level on the pedal. If you start messing with the amp controls, then it’s like trying to spin plates.
With gain pedals (overdrives, boosts, and distortions) it’s more complex but some of this advice can also be used there too.
Cheers,
Keith
