EMPIRICAL LABS DocDerr EL-RX PLUS - 500 Series - Multi-Purpose Tone Module (in EL500 Rack)

EMPIRICAL LABS DocDerr EL-RX PLUS - 500 Series - Multi-Purpose Tone Module (in EL500 Rack)

EMPIRICAL LABS DocDerr EL-RX PLUS - 500 Series - Multi-Purpose Tone Module (in EL500 Rack)

EMPIRICAL LABS DocDerr EL-RX PLUS - 500 Series - Multi-Purpose Tone Module (in EL500 Rack)

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Product Highlights

  • Six Sections of Processing
  • 3x Parametric Bands of EQ
  • 1x High Pass Filter
  • Aggressive Compressor Circuit
  • Mix Knob Blends Compressor w/ Dry Signal
  • Musically Saturates Like Analog Tape
  • EL500 Rack w/ Super Quiet 16V Supply
  • Stereo Link Switch
  • Built-In Instrument Input D.I.
  • Hand-Built and Calibrated in the USA
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Options: in EL500 Rack

Horizontal Pair in EL500 Rack

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Horizontal Version

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Vertical Version

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in EL500 Rack

This item is noncancelable and nonreturnable.

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  • 1Description

The DocDerr EL-RX PLUS from Empirical Labs is a horizontal multi-purpose tone enhancement module preinstalled in the EL500 rack that houses six different sections of digitally controlled analog processing. The DocDerr features a low-noise preamp capable of working with line level or instrument level signals, followed by four sections of EQ combining a two-position, high-pass filter with three parametric bands, each with its own set of carefully tuned frequency presets. An internal jumper can turn the DocDerr into an unparalleled instrument preamp with 16 dB of gain, great for acoustic guitar, bass, synths, exotic plucked instruments, and more.

The EQ is followed by a dynamics section which offers compression and a musical tape emulation circuit that softens and tames high frequencies and transient spikes. The DocDerr features the Mix knob, which allows the user to blend the uncompressed EQ's signal with the compressed and saturated signal. The DocDerr is great for tracking, fine-tuning tracks during mixing, and studio quality tone control.

The EL500 rack features a quiet power supply and offers both XLR and phone rear panel inputs and outputs. In addition, a 1/4" instrument preamp/direct box input is provided on the front panel, which will automatically switch the left 500 module's input to this front phone jack once something is plugged into it. Switches to link compressors and engage a 48V phantom supply are also provided.

DocDerr Module

Low noise line input, or instrument preamp, with compression and six digitally controlled analog sections of processing
Four sections of equalization including one high pass and three parametric bands
Complex compressor envelope generator that is fast, yet musically saturates at high gain reduction and features a program dependent release
Saturation circuitry that scrunches the highs, allows hotter levels, and uses filtering combined with germanium clip circuitry to soften loud high frequencies
Mix control to allow user to blend an uncompressed equalized signal back in with the compressed saturated signal (when on 0, only the equalized signal is put out)
DC coupled input and outputs
Selectable single ended or differential output (adds 6 dB gain)
Traditional and digitally controlled analog
Hard clip indicator lights illuminate when the sound level is within 1 dB of hard clipping and monitors many sections for internal clipping
All metal film and Roederstein resistors in the audio path
EL500 Rack
• Flush mount system
• Quiet 16V supplies
• More than 280 mA available on both supplies
• 48V phantom supply, 35 mA of current
• Link switch to stereo link two compressors
• Auto-sense on Inst In jack with less than .0006% THD
• XLR and phone plug inputs and outputs
In the Box
EMPIRICAL LABS DocDerr EL-RX PLUS - 500 Series - Multi-Purpose Tone Module (in EL500 Rack)
  • Power Cord
  • Limited 3-Year Warranty
  • Table of Contents
    • 1Description


    Frequency Response 3 Hz to 180 kHz on EQ section (-3 dB points)
    Dynamic Range -120 dB from maximum output (0.5% THD soft clipping) to minimum output, noise floor typically -91 dBu
    Distortion Range 0.0006 and 12% at 1 kHz
    Outputs DC coupled
    Input Impedance 120 kOhms in instrument mode, 20 kOhms in balanced line in mode
    Output Impedance 75 ohms
    Maximum Output +28 dBm
    Maximum Input Before Clipping +22 dBm, line in mode
    Attack Time 1 mS
    Release Time 0.2 seconds, program dependent, fixed internally
    Power Consumption Typical: 2 W
    Maximum: 4 W
    Power Supplies 16 V


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