What you actually bought
What this box is for, which generation it belongs to, and the one sentence that explains most of the confusion around it.
01 · 4 min
A whole guitar rig in one box, built by dropping blocks onto a grid and wiring them together. Whether it sounds right depends almost entirely on what you plug it into.
The short version
A floor processor with the same 14x6 stereo grid as the Axe-Fx III, two amp and cab pairs per preset, eight scenes and four channels per block — plus nine footswitches, nine switchable layouts, and a FASLINK II port for up to two more foot controllers.
Is this the right guide?
If yours has three footswitches it is an FM3, which allows only one amp and cab pair. If it is a rack with no switches at all, that is the Axe-Fx III.
The thing everyone gets wrong first
On a FM9, the question we see most is a footswitch that seems to have stopped working.
You are in a different layout. Layouts reassign all nine switches at once, and holding a switch usually steps between them.