Horizontal slots happen together... vertical slots can only be used one at a time. Each slot on the M9 and M13 should be though of as individual pedals on a pedal board.
Each slot on the board has it's own complete settings as far as the expression pedal goes. Nothing connects each slot on the m9 or m13... they're just like individual stomp pedals to do as you want. I was greatly over-thinking it when I got it based on past experience with Bass Pod XT's, X3's, Boss's multieffects, etc. Once it clicks that it's VERY simple it then becomes VERY simple to grasp what you can do.
If you want different settings on each you just set them seperate.
Initially I had different Octavers set up, but now I just have different ones for different tonal options and adjust each's amount with the expression pedal.
There is however two modes to saving settings. Initially it will be set up to autosave. Meaning ANY change you make to a pedal slot instantly gets saved. Sometimes thats good and sometimes bad if you change a preset you really like accidentally. The manual save mode means you have to manually save each setting before it's locked in. Which I feel is nice until you get used to the pedal.
Now I have very few problems accidentally changing things. Initially however I'd find that I'd be showing someone the coolness of the unit and start fiddling with different effects and crap and then realize that I just autosaved a bunch of wild effects over top of one of my preferred settings. Now, I'm in the habit of first changing scenes to a dummy scene I never use when I go to show off the versatility of the pedal to someone who's never seen one.
You 'can' also copy and paste settings for a slot between scenes. At least on the M13...
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