An audiologist’s goal during a hearing aid fitting is to achieve audibility. Audibility is when sounds are loud enough to be heard by patients with hearing loss. Achieving audibility is possible with hearing test results and Real Ear Measurements. Real Ear Measurements are the gold standard for verifying programming of the hearing aid according to the patient’s prescription and ear canal acoustics. Each person’s ear has a different shape and size which affects how much volume is needed to treat that person’s hearing loss. By measuring how sound builds in your ear canal, we can prevent programming mistakes such as overamplification or insufficient volume.

Types of Real Ear Measurements

Real Ear to Coupler Difference:

Difference in volume between a specific point in a person’s ear canal and in a 2cc coupler for a specified input signal.

What does this mean? We measure the shape and size of your ear canal during the hearing aid fitting. If we used an average instead, the hearing aid may be too loud or too soft. Two people with identical hearing test results but different ear canal sizes will have different prescriptions. One person with a large ear canal needs more volume than a person with a small ear canal.

Example: a radio needs to be louder in a gym to sound just as loud as a radio in a small room.

Real Ear Aided Response:

Volume at a specific point in a person’s ear canal with the hearing aid in place and turned on while listening to different inputs.

What does this mean? We play soft, moderate, and loud sounds and measure the volume coming from the hearing aid while it is in your ear. With this measurement, we program the hearing aid to match prescriptive targets. These targets are based on your hearing test and RECD.

Read more in the fact sheet PDF from ASHA (American Speech-Language-Hearing Association):
The Value of Audiologists During the Hearing Aid Fitting Process: Real-Ear Measurement (REM)