Apply an effect to only part of your sound. Drag the two lines to split it into Low, Mid and High, then set how much of each band goes through the effect. At 0% a band stays dry.
Put each split anywhere from 40 Hz to 12 kHz. Hold Shift for fine moves; double-click puts a line back.
Drag a band up or down on the display to set how much of it the effect gets. Click a band's tab to mute it, and click again to bring back the mix it had.
Every engine keeps its own split, so moving to another engine and back never loses one you set.
Reverb as a plugin of its own, 4 engines. Free updates.