Abstract: A coupling circuit composed of an input terminal for receiving an input signal from a source and first and second output terminals for supplying an output signal to a load; a signal processing device connected between the input terminal and the first output terminal for deriving an output signal from the input signal and for supplying the output signal to a load connected between the output terminals; a power supply; connecting lines each having a finite impedance and connected for supplying operating power from the power supply to the signal processing device, a distortion eliminating circuit connected between the power supply and the second output terminal for directing load current to the signal processing device so as to bypass the load current from the line impedances, the distortion eliminating device including at least one active circuit element and having an electric characteristic corresponding substantially to a capacitor with infinite capacitance.

Abstract: An amplifier circuit for applying a voltage from a voltage source across a load having a frequency domain transfer function g(s), the circuit being composed of: a coupling member having a frequency domain transfer function f(s); first connecting elements for connecting the coupling member between the source and the load; a compensating member having a frequency domain transfer function r(s); and second connecting elements for connecting the compensating member to both the source and the load.