A differential pressure gradient micro-electro-mechanical system (MEMS) microphone for measuring an acoustic characteristic of a loudspeaker. The microphone includes a MEMS microphone housing and a compliant membrane mounted in the MEMS microphone housing, the compliant membrane dividing the MEMS microphone housing into a first chamber and a second chamber. The first chamber includes a primary port open to a first side of the compliant membrane and the second chamber includes a secondary port open to a second side of the compliant membrane, and the primary port and the secondary port are tuned with respect to one another to control a pressure difference between the first side and the second side of the compliant membrane such that at least 10 dB of attenuation is observed in a microphone signal output relative to a microphone having a sealed first or second chamber.