Biggest bang: add Behringer or replace CDP?

My system consists of a Marantz CD63SE, Classé CAP 151 integrated and Maggie 1.6 speakers, in a 30' x 20' room. In the never-ending search for increased musicality at no more than moderate volume, which of the following two options will provide the biggest improvement: add a Behringer DEQ 2496 equalizer or upgrade the CDP? If the latter, I am open to suggestions for (new or used) players under $1200 US.

Many thanks.