For sale from my wife's grandfather's estate (He was a hardcore AV buff) is a vintage 1985 Pioneer SG-540 14-band equalizer. Perfect for your home set up. Easy installation via a set of RCA cables. Left and right channel frequencies set to 80, 150, 400, 1k, 2.4k, 6k, and 15k. All have +/- 10 decibels. Also has the option for EQ record out to record to an external device and the option to tape monitor to A/B your changes.
This unit is incredibly well presented for its age and should function flawlessly.