An apparatus for testing a directional hearing instrument includes: a first microphone for coupling with an output of the hearing instrument, wherein the first microphone is configured to receive an audio output signal from the hearing instrument; a first speaker for transmission of a first signal having a first frequency component at a first frequency; a second speaker for transmission of a second signal having a second frequency component at a second frequency; and a processing unit configured to determine one or more hearing instrument parameters based on cross spectrum analysis of the first signal and the audio output signal.