Four Independent Modulation Sections 
The heart of the pedal are its four, independent modulation sections synced in time, they are:
MOD features great sounding EHX Vibrato, Flanger, Chorus or Phaser. The Depth knob lets you set the amount of the effect while Feedback controls the resonance of the Flanger and Phaser.
TREM delivers tremolo, an effect that modulates the volume of your signal. The Depth control sets tremolo intensity.
PAN modulates between left and right in stereo operation. In mono operation the PAN section acts as another tremolo section, but with the wave shapes all inverted!
FILTER offers a choice of a modulated LPF, HPF or BPF. In LPF (low pass filter) frequencies above a modulated cutoff point are cut. In HPF (high pass filter) frequencies below a modulated cutoff point are cut, and in BPF (band pass filter) frequencies above and below a modulated center point are cut.
Each section also features a choice of four LFO shape options: rising sawtooth, triangle, falling sawtooth or square wave. They affect the way the modulation transitions and provide advanced creative control over the specific section as well as the way they interact with each other.

Tempo Control that’s Flexible and Powerful
The MOD REX delivers virtually limitless polyrhythmic possibilities. 
Its TEMPO component gives you nine note-length choices for each of the four modulation sections. They are independently selectable in increments starting at a whole note and ranging thru subdivisions that go up to a 16th note. In addition, any of the sections can be bypassed.
The MOD REXs tempo (displayed as beats per minute or BPM) is adjustable with the Tempo knob, Tap Tempo footswitch or by using an expression pedal into its EXP input. It can also be synced to an external device with MIDI Clock or an external pulse clock.

MIDI and the Mod Rex
The pedals robust MIDI implementation enables you to sync devices quickly and easily as well as automate functions and changes so they occur precisely when and where you want them whether you are working at home, in a studio or live.
The MOD REX accepts MIDI to enable it to tempo sync the modulation rate with an external device, to recall presets via MIDI Program Change messages and to control any parameter on the MOD REX via Control Change messages.

Extras
The MOD REX lets you save and recall up to 100 presets. It comes from the factory with xx great programs.
The pedal features full stereo input and output.
An external foot controller input makes banking up and down thru presets quick and easy.