An 
ear canal pressurization device optimized for aural acoustic 
immittance testing is disclosed. The preferred embodiment of the device is comprised of a rigid mounting framework which holds in position, axially aligned, a first flexible chamber 
assembly, a centrally disposed forcer 
assembly, and a second flexible chamber 
assembly. The forcer assembly comprises a ferromagnetic 
bobbin and coil that provides 
electromotive force for a 
moving magnet linear motor. The motor is comprised of a rigid chamber link, which passes through the 
hollow core of the 
bobbin, with a ferromagnetic keeper 
washer and axially aligned 
rare earth ring 
magnet at either end, with like 
magnetic poles facing each other. The motor is elastically suspended between the first and second flexible chambers. Current flow through the coil of the forcer assembly provides motive force for the motor via attraction or repulsion of the motor magnets and movement of the motor increases the volume of the first flexible chamber while decreasing the volume of the second flexible chamber, or vice versa. The internal volume of the first flexible chamber is coupled via an 
air line to an 
ear canal and through a controlled valve to a small vent, and the internal volume of the second flexible chamber is vented to 
ambient air pressure. Changes in volume of the first flexible chamber, due to 
motor movement, produce changes in 
ear canal pressure re Boyle's law. The vent may be opened to allow ear canal pressure to gently equalize to 
ambient air pressure or to generate ear canal pressure sweeps free of pressure baseline offset. The vent may be closed to set a static ear canal pressure or to generate ear canal pressure sweeps with an incidental baseline offset. The vent may be controlled to generate ear canal pressure sweeps with an intended baseline offset. The device produces ear canal pressure proportional to drive 
voltage, so any desired pressure versus 
time function can be generated by applying a coil driving 
voltage with the appropriate amplitude versus 
time function. The device operates quietly to avoid interference with aural acoustic 
immittance measurement, and should have a long and maintenance free 
life span.