Madsen impedance meter

Madsen impedance meter

[′mad·zən im′pēd·əns ‚mēd·ər]
(engineering)
An instrument for measuring the acoustic impedance of normal and deaf ears, based on the principle of the Wheatstone bridge.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.