So I'm going to be doubling for the first time soon. I've been experimenting with A/B switching. What I am thinking about doing is running an A/B switch between the fender and the upton, but running all of the pedals/pre's that I would use in a single chain. I would then just switch off the section I need when I switch instruments. Do you guys see any problems with this? Basically I'll run what's shown as my UPRIGHT SIGNAL CHAIN until it's bass guitar time. Then I'll mute, click off the three components in that chain, switch to channel B, switch on the VT bass, then unmute.