The MA100H is powered using the traditional Marshall mainstays of ECC83 double triode tubes in the preamp, and EL34 pentode tubes in the power amp. The layout and controls are kept simple, allowing you to explore unhindered the full potential of the all-tube tone within. The MA100H has separate EQ stages for both the Clean and Overdrive channels so you can optimally adjust each one without compromising the other. An extra benefit has been provided in the form of a tube-driven Boost function on the OD channel giving you, for example, a solo boost with more volume and gain. The amp also contains a spring reverb for use with all channels within the amp..