The DBX's 520 de-sser is a signal processor that tame harsh sibilance. Even if your signal level varies greatly, the 520 provides precise sibilance control, making it an easy set-and-forget processor for tracking, mixing, and live sound applications. With comprehensive metering and a de-essing range of 800Hz to 8kHz, Vbizz recommends the 520 module for softening vocals, cymbals, and any other harsh source. Every serious audio engineer needs a good de-esser in their rack, and the dbx 520 de-esser module will serve you well.