Empirical Labs ELDS-V DerrEsser

500 Series Dynamic High Frequency Fixer

The DerrEsser is a multi-function dynamic filtering device, in an API 500 series module format. In its basic “DS” mode, the DerrEsser is an effective, level-insensitive de-esser, which is a device that will adjust the high-frequency gain on overly trebly or spiky vocal, or other source. By using a crossover technique, and dividing the audio up into a high frequency range and a low frequency range, the DerrEsser can use its Voltage Controlled Amp to turn down comparatively high or harsh high frequencies in an extremely musical manner. However, unlike other de-essers, the device is not limited to just de-essing, and allows for multi-use of its circuitry.

The DerrEsser Has Four Modes

• DS Mode: (Bypass Button IN, all other buttons OUT). In DS mode (HF Limit OFF), the DerrEsser acts as a level-independent de-esser, taming harsh sibilants from an overly bright singer or aggressive EQ. The DS threshold compares high-frequency content to low-frequency content, so adjusting overall level does not affect it. Easy to set and forget.
• HF Limit: (Bypass Button IN, HF LIM IN, all other buttons OUT). This mode acts as a high-frequency compressor. If the high-frequency content exceeds the threshold, gain reduction occurs. This is the first carefully tailored soft knee HF limiter in existence.
• Highpass: (Bypass Button IN, Listen IN, HP/LP OUT, HF LIM doesn’t matter). In LISTEN mode, with the HP/LP switch OUT, the user hears the high frequencies being controlled by the dynamic/compression circuits. The corner frequency is adjustable by the Frequency knob.
• Lowpass: (Bypass Button IN, Listen IN, HP/LP IN, HF LIM doesn’t matter). In LISTEN mode, with the HP/LP button IN, the user hears the low frequencies unaffected by the VCA and dynamic/compression circuits. The corner frequency can again be adjusted by the Frequency knob.

• Frequency Response: 3 Hz to 120 kHz (-3dB points).
• Dynamic Range: 115 dB from maximum output (.5%THD soft clipping) to minimum output. Transformerless noise floor typically –93dBu.
• Distortion: Ranges between .0035% and .01% depending on mode and settings.
• I/O: DC Coupled input and outputs. Input Balanced, Output single-ended but with balanced impedance. Pin 2 hot.
• Impedance: Input impedance is 20k Ohm. Output impedance is less than 51 ohms.
• D-S Dynamics Time Constants: Attack time is less than 1mS. Release .04 sec, fixed internally.
• Power Consumption: 8 Watts max. 4 Watts Typical.