The dbx 166XL Dual Compressor Limiter Gate at Front End Audio. The dbx 166XL provides 2 channels of noise gating, OverEasy or classic hard knee compression and PeakStop limiting to give complete control of signal dynamics to studios, sound reinforcement companies, musicians, or anyone who needs quality processing quickly and easily. We recommend that you take a moment and read through the manual as it provides information that will assist you in using your unit to its fullest potential.