How many amps can an FM3 preset have?
One amp and cab pair. The FM9 and Axe-Fx III each allow two, and that is the single clearest difference between them.
Reference
Reference
Questions and answers
The things people actually ask about the FM3, answered in a sentence or two, with a link to the detail.
Is three footswitches enough?
More often than it sounds, because layouts reassign all three at once. If it is not, FASLINK II takes one or two FC-6 or FC-12 controllers over a single XLR cable.
Why did my FM3's footswitches change job?
You are in a different layout. It boots into the Presets layout, and holding the left or right switch moves through preset banks.
What's the difference between a scene and a channel?
A scene is a snapshot of the whole preset — what is bypassed and which channel each block is on. A channel is a variation inside one block, four per block. On an FM3, channels matter more than anywhere else, because they are how you get variety out of one amp block.
Can I run two instruments into an FM3?
You can plug them in, but with only one amp and cab pair the processing options for the second are limited. Fractal say so directly.
Which output goes to my amp?
Output 2 — it is the quarter-inch pair, with Humbuster wiring. Output 1 is XLR only.
How do I get rid of hum going into my amp?
Use a Humbuster cable from Output 2 — TRS at the FM3 end, TS at the amp.
Can I use Input 2 as both a loop return and an aux input?
No, one or the other. It is a single stereo jack pair doing two jobs.