Replacing my FET power amplifier that drives my “Studio Mains”. Upgraded the reserved 2U space in my rack with the Mesa Stereo Simul-Class 2: Ninety. I’ve choosen the second version of this Mesa because on the back of the unit you will see a selector switch for Instrument/Line & Lift/Ground. This allows me to easily integrate. Soon I will construct a custom foot-switch to change amp modes. Below you will find some inside unit photos and the manual.
Mesa Ninety I 
Mesa Ninety II