Walrus Audio Fable MKII Guitar Effect

Stereo Granular Soundscape Generator for Ambient and Experimental Players

The Walrus Audio Fable MKII Gray is a stereo ambient creation machine built around delay and granular micro-sampling. Each of the five onboard modes pairs two effects in series, then routes the signal through two independent feedback paths so the texture keeps evolving instead of repeating. Long reversed swells, bright double-speed cascades, glitchy clouds, and randomized pitch scattering are all available from a single stompbox-sized enclosure. MIDI clock, expression pedal input, and 3 onboard presets plus 127 more over MIDI put deep control in the hands of sound designers and ambient guitarists.

Five Granular Modes and Dual Feedback Architecture

What sets this pedal apart is the dual feedback path developed by Walrus Audio's DSP engineers. The signal runs through two separate effects in series, independently controlled by the Feedback and Regen knobs, then loops back through both again before reaching the output. Mode I pairs reverse delay with reverse granular for shifting textures; Mode II stacks forward delay with octave-up granular for bright, airy cascades; Mode III combines analog-style delay with octave-down granular for deep, murky footfalls; Mode IV runs two multi-tap granular algorithms in series (the Grain-Verb) for cloud-like ambient pads; Mode V feeds forward delay into randomized pitch granular where each grain plays at a randomly selected speed and direction.

Tweak Knob and Dive/Rise Modulation — Player-Facing Controls

The Tweak button cycles a single knob through five parameters, giving players access to deep sound shaping without menu diving. Width spreads the wet signal across the stereo field, Mod Rate runs an LFO from 0.1 Hz to 5 Hz, and Mod Shape selects sine, square, or random waveforms. Shift sets the Dive/Rise target anywhere between 0.5x and 2x, while Ramp controls glide time from 50 ms to 5000 ms. Holding the tap footswitch momentarily shifts the clock rate up or down for instant pitch dives or rises.

• Tweak Parameters: Width, Mod Rate (0.1–5 Hz), Mod Shape (sine/square/random), Shift (0.5x–2x), Ramp (50–5000 ms) — five deep controls from one knob
• Dive/Rise: Momentary tap footswitch — instantly pitch-shift the clock up or down for as long as it is held
• Presets: 3 onboard (red, green, blue) + Live Mode + 127 via MIDI — full recall of knob positions and expression assignments

Connectivity and Signal Flow — Stereo I/O and MIDI Integration

True stereo operation runs from two unbalanced 1/4" inputs to two unbalanced 1/4" outputs, with mono-in/stereo-out also supported for thickening a single guitar signal. The 1/8" TRS Type A MIDI In and MIDI Thru jacks accept clock for delay synchronization across Modes I, II, III, and V, and drive sample-rate time-stretching in Mode IV. Every knob is exposed over MIDI CC, and any knob can be assigned to the expression input, or the jack can be set up as an external tap input. A USB-C port handles firmware updates.

• Audio I/O: 2 x 1/4" unbalanced input, 2 x 1/4" unbalanced output, 1 MΩ input impedance, 220 Ω output impedance — full stereo path or mono-to-stereo widening
• MIDI: 1/8" TRS Type A In/Thru, MIDI CC for all parameters, MIDI clock 100–1000 ms delay range — integrates into any MIDI pedalboard or studio rig
• Expression: Assignable expression jack or external tap input — saved per preset for hands-free morphing

Build, Power, and Bypass — Hardware Specifications

The enclosure measures roughly 100 x 119 x 58 mm including knobs and ships with original artwork illustrated by Niall Grant. Buffered bypass is selectable between Trails (default, lets feedback decay naturally) and No Trails (cuts off abruptly). Power comes from a standard 9 VDC center-negative supply at 300 mA minimum, and Walrus Audio recommends an isolated power supply rather than a daisy chain. The wet signal path runs at a 32 kHz sample rate.

• Dimensions: approx. 100 x 119 x 58 mm — compact stompbox footprint that fits standard pedalboards
• Power: 9 VDC center-negative, 300 mA minimum — isolated supply recommended
• Bypass: Buffered, Trails or No Trails selectable — Trails mode lets ambient textures decay naturally when the effect is switched off