NU-X A/B Roll Octave & Looper Guitar Effects PedalNU X A B Roll Octave & Looper Step onto the next level of recording overdub. The NUX A B ROLL Octave & Loop pedal is more than just a looper its a musical ode to the legendary studio that inspired its design, where some of the most iconic recordings in music history were made: Abbey Road Studios. This versatile, compact unit combines polyphonic sub octave and AUTO recording capabilities with IR cab simulation, bringing the magic of in the moment