A MOST COMPLETE AND USER - FRIENDLY BATTERY OF TESTS The A766 offers a most complete battery of tests. This allows designing the test strategy best suited for the individual patient, from rapid screening to clinical tests, to functional investigation on acoustic and non acoustic reflex, the latter evoked by non acoustic stimuli. The extreme flexibility of the A766 program allows performing an additional ETF test in intact TM subjects, the "Valsalva maneuver" that consists in the forced expiratory effort with closed nose and mouth to inflate the Eustachian tubes and the middle ears, useful to study the ability to compensate sudden pressure increases. The parameters can be modified during test session without permanently saving them. The user - programmable parameters can also be customized and permanently saved. TYMPANOMETRY - MANUAL AND AUTOMATIC Automatic Tymp pressure range and velocity are user-programmable; they can be modified and saved. Manual Tymp allows storing tympanogram peak to perform manual reflex tests.