I was wondering if anyone knows a way to map a parameter to be controlled by two knobs, each controlling half the parameter. For example, the built in filter in Traktor's mixer: can I control the high pass part with one knob and the low pass part with the other knob?

Ultimately what I want to be able to do is have one knob for the filter and then another knob acting as a modifier to switch between high pass and low pass mode