Hi Jae Hwan, One way to split Main L & R and EQ them separately is to use the mono Matrix section. Here's how: Assign the L channel to Matrix 1, and the R channel to Matrix 2. If the C channel is being used route it to Matrix 3. Then patch the Matrix outputs, instead of the Mains outputs, to your speaker processor. On the Options > Pickoffs page I recommend the following settings: Matrix Source LCR = Post-Fader Master Insert Points LCR = Pre-Fader (these are the defaults, BTW) This configuration allows you to still use the Mains fader as the master level control, while also giving the option to insert an additional stereo GEQ across LR for "global" changes you want to happen to both sides identically. Sheldon