NAL-NL2
Pronunciation: nal-en-el-too
Also written as: NAL-NL2 — National Acoustic Laboratories Non-Linear version 2
A widely used prescriptive hearing aid fitting formula developed by the National Acoustic Laboratories of Australia that calculates target gain and frequency response for a given audiogram.
Full Definition
NAL-NL2 (National Acoustic Laboratories Non-Linear version 2) is a second-generation prescriptive formula that specifies the optimal frequency-gain characteristics for a hearing aid based on the individual's audiometric thresholds, age, sex, and language experience. It is designed to maximise speech intelligibility while maintaining comfortable loudness and is the most widely referenced fitting target in adult audiology research. Editors must verify that 'NAL-NL2' is styled with a hyphen and the numeral 2, not 'NAL NL2,' 'NALNL2,' or 'NAL-NL II.' Its predecessor, NAL-NL1, is still cited in older literature, and distinguishing the two versions in edited documents is important. DSL (Desired Sensation Level) is a competing prescriptive method, particularly dominant in pediatric fitting.
Usage
Usage note: Style consistently with hyphen and arabic numeral: NAL-NL2. Do not substitute Roman numeral II. Contrast with DSL when the fitting target for pediatric populations is discussed.
In Context
- "All participants were fitted to NAL-NL2 targets and verified using real-ear measurement." — Research article methods section
- "The editor queried whether 'NAL-NL2' or 'NAL-NL1' was intended, as the cited publication pre-dated the release of the second formula." — Editorial query on manuscript