Mad Professor launches Simble MKII overdrive pedal

June 3, 2025 · 2 sources

Mad Professor unveiled the Simble MKII, a revised version of its Dumble-inspired overdrive pedal, on June 3, 2025¹². Both MusicRadar and Gearnews reported the launch the same day, describing improved headroom, greater clarity and the same transparent sound as the original¹².

The pedal has four controls: Level, Contour, Attack and Sensitivity¹². The Attack dial shapes the tonal response of the overdrive, and the Contour dial is neutral at 12 o'clock, brightening or darkening the output to taste¹². MusicRadar reported that the Contour control was cleaned up from the original after some players found it muddy with certain guitars¹. The Sensitivity knob adds overdrive and compression, and it is where the new circuit design by Lassi Ukkonen is most audible; the design was tweaked to improve string clarity, particularly when drive is maxed out¹².

MusicRadar described the pedal as able to work as a clean boost, an "on the edge" crunch or a singing overdrive, and said it suits single-coils, humbuckers and P-90s¹. Gearnews said it can be dialed in as a clean boost to push the front end of an amplifier². The enclosure has been redesigned, with the faux wood panelling of the original replaced by a deep red finish with cream text and black dials¹.

The Simble MKII runs on 9V DC and draws 10mA¹. It is available now¹. 00 at Thomann². MusicRadar noted that the pedal is inspired by Dumble guitar amplifiers but is not marketed as such, and that Dumble owners such as Kenny Wayne Shepherd say even Dumble clone amps are not quite like the real thing¹.