Meet groc

Groc has a left side and a right side, separated by the display, and 3 rows of grouped encoders with an associated toggle on each side. Once you have learned the functionality of these 6 groups of encoders and toggle, then you groc. Let’s explore:

On our right: synthesis and modulation

The toggle on the left switches between A (LED off) and B (LED on) modes. In A mode, you can twist one of the encoders to adjust the attack, decay, sustain and release of one of four envelopes. The illuminated encoder indicates which envelope is active, and a press on any encoder selects the corresponding envelope - 1, 2, 3 or time path. Envelope 1 controls the amplitude envelope of the note (by default). As is typical, the encoders control the sustain level and the attack, decay and release times, where the times define how a voice advances through a set of states, or regions of a note (i.e. the attack, decay, sustain, and release regions). The Time Path envelope (on the rightmost encoder) is different from the others. When time path is selected, the encoders control playback speeds for the corresponding region of the note (attack, decay, sustain, release). Envelopes 2 and 3 are available to modulate parameters (e.g. a filter cutoff) and behave similarly to envelope 1, however without the connection to the time path. In B mode, the encoders adjust the audio sample start, loop and crop points.

And the left: effects and system controls

Groc has a pair of filters and a saturation processor at four locations in the signal chain (see the blocks labeled “filters & saturation” in the diagram below). These are not mutually exclusive; they all can used concurrently to achieve different outcomes. Each filter can be low pass, high pass, band pass, band stop, low shelf or high shelf. Each pair of filters can be used in series, parallel or left-right split modes. Each saturation processor can be a distortion, compressor, limiter, expander, gate or other non-linear functions. You can even draw your own waveshaping function on the touch screen. At each of the four locations, the saturation processor can be placed either before or after the filter pair.

In A mode (LED off), the two encoders control one filter’s cutoff and resonance. The illuminated encoder indicates which filter is active, and a press selects the corresponding filter - 1 or 2. The types of filters, whether the filters are in series, parallel or left-right split, and which of the four sets of filters are being controlled are all adjusted from the touch display. In B mode (LED on), the encoders control the drive and linearity (a mix between unprocessed, or “linear”, and processed, “non-linear”). Again, the type of saturation, whether it sits before or after the filters, and which location in the signal chain are all changed with the touch display.

The echoes and harmony section is like having a tape echo and harmonizer handy. Sitting in the processing chain after all the sound generated by active voices is combined, a “echo and harmony path” (e&h path) consists of a time-delay processor, a pitch-change processor, and a feedback path including a “filters and saturation” section (see above). With pitch change, filters and saturation off, get pristine digital delays up to 1s long or micro-second delays for classic phasor effects. Add in the filters and saturation to create lovely analog delay sounds or walls of distorted feedback. Leave the delay off and use the pitch change for subtle chorus, vibrato, or harmonies up to 2 octaves from the unprocessed pitch. And yes, feel free to start delaying, pitch-changing, distorting, filtering and feeding back together. With so much achievable, why did we add a second one? Making chords and ping-pong delays, among other things.

In A mode (LED off), the two encoders control the feedback and time delay for one of the echo and harmony paths. In B mode (LED on), the encoders control the pitch change and the level of the e&h path relative to the dry signal. The illuminated encoder indicates which e&h path is active, and a press selects the corresponding e&h path - 1 or 2.