CMOS Bass Overdrive. The Microtubes B1K is a phenomenal tribute to one of our most legendary distortion circuits in a compact and intuitive format. We are proud to introduce our Microtubes B1K distortion pedal, the first of its kind from an all-new lineup. Front | Level Sets the volume of the overdriven signal. Front | Drive Sets the amount of saturation in the overdriven signal. Back | Blend Mixes the clean input signal with the overdriven signal. The clean signal is fixed at unity gain, while the volume of the overdriven signal is set by the Level knob, allowing for fine control of the blend ratio. Turn clockwise to blend in the clean signal. Back | Tone Controls the high frequency content of the sound. A variable low pass filter from 3 kHz to 8 kHz. Turn CCW for a brighter sound. Back | MBoost Gives a subtle 6 dB boost from 300 Hz to 1 kHz to help you cut through the mix. Back | Grunt Provides a low-end boost to massively thicken your sound when engaged. DIMENSIONS Width 50 mm (2 in) Height 100 mm (4 in) Depth 45 mm (1.75 in) Weight 205 g (0.45 lb) WARNING: The Microtubes B1K has a current draw of 30 mA. Only use a regulated 9V DC adapter with a center-negative plug. Due to ecological reasons, it does not accept batteries. Unregulated power supplies and/or higher voltages may result in suboptimal noise performance and even damage your unit, voiding the warranty.