Benson Portable Distortion 424 MkII The Benson Portable Distortion 424 MkII is a masterclass in nostalgic tone design, distilling the famously imperfect sound of a 424 cassette 4-track recorder into a portable, pedalboard-friendly format. More than a simple distortion, it functions as a full preamp and tonal management system, offering a remarkably versatile gain range that spans from a clean, characterful boost to sizzling overdrive and full-blown, lo-fi saturated fuzz.