i explain better my needs. actually i power the mf1 by phantom power thru the herbert. so in this case powering the mf1 is not an issue.
if for example i have to go to reharsal room without my herbert and i want to use the rocktron Xpression rack effect and midi pedalboard mf1, i need to power the mf1 by a power supply.
in addiction, i'd need another p.syupply for the wha and some other pedal.
that's why i'd need a multiple power supply. i hate the idea to have 3500 single power supply.
9-12 means that you can put 9 or 10 or 11 or 12 V DC into it.
It doesn't matter, it is rectified and regulated anyway inside the MF1.
From the PowerPlant you could use the 12V DC 250mA for the MF1 (don't worry about the 250mA - its enough) and 9V for the wah. Or feed both units off the 9V outs.
And seriously - 25 posts here for a power supply . . .