Empirical Labs EL-Rx DocDerr 500 Series Multi-Purpose Tone Module Vertical Faceplate

It’s all about TONE. The DocDerr is a digitally controlled Preamp, EQ, Compressor and Saturator module good not only for general use, but can single handedly bring incredible tone to any source, even electrified acoustic instruments. It offers unprecedented amounts of processing and musicality in an API 500 compatible module. With a mini-computer inside (Microcontroller), one controls 4 analog EQ sections, and a new dynamic section capable of chopping brittle edges and digital transients with its compressor and saturation circuits.

The signal route begins at an extremely 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 un-paralleled instrument preamp with 16dB of gain, ideal for acoustic guitar, bass, synths, exotic plucked instruments, etc.

The versatile EQ is followed by a unique dynamics section which offers renowned Empirical Labs compression at an unprecedented price, and an extremely musical tape emulation circuit that softens and tames high frequencies and transient spikes.

One of the pivotal features of the DocDerr is the “Mix” knob, which allows you to blend the uncompressed EQ’s signal with the compressed and saturated signal. This parallel compression technique, used by top recording and mixing engineers for many years unlocks a whole world of sonic possibilities.

Like all ELI 500 series modules, the EL-Rx is available with either horizontal or vertically oriented front panel configurations, and is “Linkable” for using our famous compression on stereo sources.