Methods are provided for solid-state implementation of a vacuum tube replacement device (VTRD) that includes a communication interface. The communication interface enables the VTRD to command or retrieve information regarding VTRD performance, function, and status. A VTRD may communicate with other VTRDs in a target amplifier retrofitted with compatible VTRDs and to an external user interface for programming or query/response. The methods presented for the vacuum tube replacement device system(s) are equally useful for non-vacuum tube systems such as audio amplifier circuits.