Using MultiEQ XT to EQ "Front B" Speakers

I have a Denon AVR-2312CI with a 5.1 speaker system for music and movies. The EQ work is stellar and I find the speakers that I chose (passive Behringer B2030P) to be very revealing and detailed, perfect for home theater. For music , however, I feel that they are not very enveloping in two channel mode and the soundstage seems a little flat. I suspect this is due to their constant/narrow directivity design which reduces room reflections. I want to add a pair of dedicated music speakers and use the Denon internal amplifier set as Front B. Can I use MultiEQ speakers to EQ the speakers even if they are not surround back channels? How would I go about EQing the second set of speakers for two channel listening? One idea i had was to simply assign the amplifier as surround back for those channels and set the second set of speakers in the preferred listening position. Once the EQ work is done I can simply reassign the channels for front b duty. Thanks for your help.