An assembly of electronic reference devices intended to calibrate and/or test the calibration of an audiometer. It measures the sound frequency and intensity characteristics that emanate from an audiometer earphone and/or the environment (ambient noise). The system typically consists of an acoustic cavity of known volume, a sound level meter, a microphone with calibration, oscillators, frequency counters, microphone amplifiers, and a recorder. It can measure selected audiometer test frequencies at a given intensity level, and selectable audiometer attenuation settings at a given test frequency.