A signal modification circuit is provided for use with multi-mode formatted data in accordance with a common mode component and a high frequency component formatted in accordance with a differential mode. The circuit includes an active module that modifies the high frequency component to generate a modified and enhanced high frequency component at an output thereof. A bypass line interconnects the inputs and outputs of the active module to bypass the active module. A low pass filter is provided along the bypass line blocking passage of the high frequency component along the bypass line.