DOD SR231QXLR Graphic EQ DOD's flagship equalizer, the SR231 QXLR combines two constant Q, 31-band, 1/3 octave equalizers into a two rack space steel chassis The back panel boasts XLR, and 1/4 inch connectors With a fully shielded internal power supply, and unsurpassed specifications, the SR231QXLR is the perfect choice where ever stereo