A calibration device and method of manufacturing the same. The calibration device for a hearing earpiece configured to at least partially protrude into the ear canal of a user includes a calibration base. The calibration base a calibration insert. An air chamber is defined between the calibration base and the calibration insert. The calibration device also includes at least one earpiece receiving mechanism defined on the calibration insert. The at least one earpiece receiving mechanism is configured to create an sealed connection between given ear piece and the air chamber for calibration. The earpiece receiving mechanism is configured to at least partially receive the given earpiece. A corresponding method of manufacturing is also included.