The dbx® 2-Series Graphic Equalizer series have been designed to meet the needs of the most demanding sound reinforcement environments, while offering the simplicity of straightforward controls. The 131 not only offers standard features like single-channel, 31, 1/3 octave bands, ISO frequency centers, +/- 12 dB input gain range, and switchable 50Hz/12 dB per octave low-cut filter, but also includes other insightful features. These features include 20 mm faders; selectable +/-6dB or +/-12dB boost/cut range for precise gain adjustments; XLR, and 1/4'' TRS connectors for installation ease; balanced inputs and outputs for quiet operation. The visionary design of the dbx 2-Series makes your job easier.