So you are unbalanced coming out of the AVR (RCA).
I have no idea about your EQ. Post some pictures and descriptions of it (back of it, I don't care what the front looks like)and I will take a look at it when I get back from the gym.
The EP2500 only accepts XLR or 1/4 inputs so depending on what your EQ offers, you will have to have a way to convert the RCAs to XLR or 1/4. This can be done via cables for unbalances or with something like an ART Cleanbox for balanced.
For Mono bridged out, remove the speaker terminal cover on the 2500 and use the middle post. It is clearly detailed in the manual. The toggle switches are also explained in the manual. Just look at that page, decide how you want to run it and flip the switches.