When a Real Ear Measurement probe tube is placed into the adult ear canal and a REUR test performed, we expect to see a typical result in associated with a typical anatomy of an adult ear. This is reflective of an ear (i.e. pinna, concha and external ear canal) that has an approximate ear canal length of 28mm and is essentially a tube closed at one end (by the tympanic membrane) and open at the other. Those that are younger (with shorter ear canals), or have had modifications to the ear anatomy through surgery or trauma, will not necessarily have the typical result.
The typical adult ears natural resonance response produces amplification of incident sounds in the frequency range of around 1500 Hz to 7000 Hz, with a peak at approximately 2700 to 3000 Hz. When we review a REUR, this peak typically occurs with approximately 10-20dB of gain. An additional feature of the typical adult REUR is that there is little or no amplification below 1500 Hz.
The below graph displays an average REUG result in a typical adult ear canal.
REUG for “typical” adult ear taken from Interacoustics Affinity Suite software
An REUR is the same concept as a REUG but is displayed in dB SPL.
Related course: Getting started: Real ear measurements