The DerrEsser ELDS-V from Empirical Labs is a vertical multi-function dynamic filtering device, designed for API 500-Series enclosures. In its basic DS mode, it is an effective, level-insensitive de-esser, a device that will adjust the high-frequency gain on overly treble-y or spiky vocals or other sources in an extremely musical manner. However, unlike other de-essers, the device allows for multiple uses of its circuitry. As a de-esser in the DS mode (HF Limit OFF), the threshold can be set to tame harsh S’s (sibilants) that result from an overly bright singer or from EQ’ing to make a vocal sound aggressive and clear. The DS threshold is not level dependant, and compares the amount of high-frequency content to the low-frequency content, so adjusting the overall level does not affect the threshold. It features VCA technology for glitch-free, distortion-free, and noise-free performance. The corner frequency is user adjustable with a high-performance active crossover.