Hello,

I know there are 4 modes, (5 with the "Direct Recording" mode):

- A - feeding a power amp input - closed back (ideal for 4x12 cab)

- B - feeding a power amp input - open back (ideal for 1x12)

- C - feeding an instrument input - open back (ideal for 1x12 or 2x12)

- D - feeding an instrument input - closed back (ideal for 4x12)

But what exactly do they do?

Is it just an EQ?

I have a closed back 1x12 and a Electro Harmonix 22 Caliber amp. It is a small guitar head, and they call it a power amp. Which is why I'm hesitating between all 4 presets.

I quickly tried them all, and I found that the default one (C) wasn't that bad.