DBX 231s Silver 31 Band Dual Channel EqualizerWhen the pros need an EQ, they turn to dbx. With a proven track record that spans four decades, dbx EQs are the industry standard for touring, studios, and audio installations. With the dbx heritage of revered pro EQs, the 231s meets the needs of the most demanding sound reinforcement environments, while offering the simplicity of straightforward controls. The dbx 231s includes two 31 band channels of 1 3 octave equalization, 12 dB input gain,