You still need the Midi Jacks from them actually, they connect on the back.
I love the big knobs! Check out the Ikarie Filter though. Everyone is crazy about it these days. It has stereo capabilitys and a built in VCA. This could pair well with the AUX and OUT of your Plaits and the Quadra. Or maybe the Dual Dagger Stereo Filter. This has a HP filter that also processes the signal. That way you can already cut some of the low end and have a cleaner mix/patch. The Ikarie has an HP too though, I do not have the funds atm so i did not go into it too deeply. But I will get either of those next year probably.