The Acceptable Noise Level (ANL) Test

Predict Hearing Aid Success!

Perform the Acceptable Noise Level Test to predict whether a person will be a successful hearing aid user.

What is the ANL Test?

The ANL is an audiometric test that predicts whether or not a person will be a successful hearing aid user by finding out how well they tolerate noise in speech signals. Research shows that the better a person tolerates noise, the more likely they will be a successful hearing aid user.

How does the test work?

The ANL speech passage is normally presented to the patient in a sound booth using sound field speakers, but it can also be performed with headphones. The clinician determines the MCL. Noise is then gradually added to the speech passage in increasing levels until the patient indicates the noise reaches a level that the patient would not be willing to listen to for an extended period of time. The ANL score is determined by subtracting this noise level from the MCL. Patients with a low ANL score are very likely to be successful with hearing aids. Patients with a high ANL score do not tolerate noise very well and may be difficult to fit successfully without a lot of extra counseling.

How accurate is the ANL?

Clinical studies have shown that the accuracy of the ANL prediction is 85%.

How long does the ANL Test take?

The ANL Test typically only takes 2-3 minutes.

What options do I need on my audiometer to perform the ANL Test?

It is recommended that you have a sound booth that meets ANSI requirements. The speech and noise signals are typically presented using a sound field speaker at 0 degrees azimuth, although headphones can be used in a pinch. You will also need an external CD player and some way of communicating with the patient such as a patient response switch or a talkback microphone.

*ANL is manufactured and distributed exclusively by Frye Electronics, Inc.

Step-by-step instructions for using ANL with the FA10/FA12 audiometer (pdf)

Generic instructions for using ANL with a clinical two-channel audiometer (pdf)