Clinical maskers must be wider than the critical band to work

Evidence

When masking pure tones in clinical applications, the maskers used must exceed the critical band. A masker narrower than the critical band would be insufficient as a masker for diagnostic audiology. Typical maskers used in audiometry are wider than the critical band in order to take into account individual differences and to ensure sufficient masking even at high stimulus levels. • Masker effectiveness. The size of the critical band is a necessary component to determine how effective a masker can be. Because the audiologist is interested in the effectiveness of the masker rather than its total power, maskers are considered in terms of their effective masking level, dB EML. The effective masking level is the dB HL value to which threshold is shifted in the presence of a noise at that dB EML. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 583

Categorization

• DEFINE: Defines effective masking level (dB EML) as the dB HL to which threshold shifts under a noise.