The Ingram Engineering MPA201 provides two channels of semiconductor based 100% discrete two-stage amplification of microphone signals. Amplification is provided by all-discrete JFET input / Class-A Output circuits. This unit has a fully balanced design from input transformer to output transformer and has the highest voltage rails that will likely ever be encountered for a semiconductor design. A combined variable-attenuator/gain stepped switch control at the input provides the ability, unique among most pre-amp designs, of optimizing signal to noise and dynamic range for any audio signal level. A high current Class A buffer drives the output transformer.