Edit tl;dr:
- Guitar volume: leave on full
- Gain control: control amount of overdrive/distortion
- Channel volume: adjust patch volume level
- Master volume: adjust overall sound level
Referring back to the original question, as well as trying to encompass some of the other questions on this thread…
It may be good to step back and try to understand what is happening when you use an electric guitar and an amp.
Basically, you have a signal chain going from your guitar, to the amp, through the amp circuits, to the speaker. Along that chain you have a number of controls which alter that signal. Because it’s a chain, then each control only alters what came before it.
So, the basics of any electric guitar and amp are:
The “volume” (it really should be called “level”) control on the guitar sets the output level from the guitar pickups to the amp
The Pre-amp stage of the amp receives that signal and amplifies it. The gain control on the amp controls how much it amplifies the input signal by.
If you turn the gain up, it will start to cause the pre-amp circuit to exceed it’s maximum capability, which will distort the sound. On a hifi amp, this is a bad thing. On a guitar amp, this can be a good thing, and is known as “overdrive”. Different types of pre-amp will overdrive at different levels. This equates to the “amp type” control on the Katana.
So, for instance, if you set the guitar output to halfway, and then set the Katana to Crunch and set the gain so that the sound is quite “clean”, then if you turn the guitar volume up to full, it will be driving more signal into the pre-amp, which will cause it to overdrive. A lot of guitar players use this to easily switch between a clean and overdriven sound.
So the interaction between the “volume” control and your guitar and the input gain on your amplifier gives you control over the level of overdrive.
Of course, it also impacts the sound level, but controlling the sound level from your amp using these controls is not the right thing to do in general.
Most amps have some sort of volume control on them, and some amps (like the Katana) have two. These control the sound level output of the amp and it is these controls you should generally be using to control how loud the amp is. These controls should not “colour” (change) the tone in any way, but should just impact the sound level output from the amp speakers).
In other words you should NOT (generally) be using the “volume” control on your guitar to control how loud your amp is. This knob is (generally) most useful for creative use, but I would suggest that beginners should not worry abut that whilst they are learning everything else.
Which is why this is the best advice:
Otherwise, as a beginner, you are juggling too many controls, which will get in the way of your learning.
If your amp is too loud, turn down one of the amp volume controls. In general, start with the master volume.
On a Katana (and some other amps) there are two volume controls: “channel volume” and “master volume”.
Master volume is used to set the final, overall, sound level output from the power amplifier section of the amp through the speaker. If the amp is too loud, start by lowering this.
Channel volume (which, on the Katana, is in the “Amplifier” section on the left of the panel), controls the level of the output from the pre-amp to the power amp.
Because, again, it’s a signal chain, increasing the channel volume will push more signal into the power amp and make it louder, which means you may have to turn down the master volume.
Basically, for amplifier sound level, you need to use the channel volume and master volume to control this NOT the gain or the guitar “volume” knob:
- Leave the guitar “volume” on full (just use it to mute the guitar by turning it fully off)
- Use gain to set the level of “crunch”, “overdrve”, or “distortion” you want
- Balance the channel volume and master volume to get the sound level you want
As to why there are two volume controls (channel volume and master volume), the main reason on an amp like the Katana is that you can use this to offset the changes in volume caused by adjusting the gain control.
The idea is that, once you have adjusted the master volume to get a general sound level you like, if you change the gain and this causes the sound level to increase, offset this using the channel volume.
On an amp like the Katana with patch memories, this is specifically useful as the channel volume is stored with the patch: the idea here is to set each patch volume so that, when you switch between patches, you don’t get a massive increase in sound output level.
In this way, you can then use the master volume to control how loud the amp sounds in general, and not have to mess around with any of the other controls.
Getting to that point will require a bit of experimentation though.
For reference, I attach a picture of the Katana top-panel controls.
Cheers,
Keith
I’m sure someone will correct me if I’m wrong.