NEN EN ISO 389-4 : 1999
Current
The latest, up-to-date edition.
ACOUSTICS - REFERENCE ZERO FOR THE CALIBRATION OF AUDIOMETRIC EQUIPMENT - PART 4: REFERENCE LEVELS FOR NARROW-BAND MASKING NOISE
01-12-2013
Defines reference levels for narrow-band masking noise presented by air conduction from an earphone in pure-tone audiometry. Data given is in terms of levels to be added to the reference equivalent threshold sound pressure levels for the corresponding pure-tone frequencies as given in ISO 389:1991 or ISO 389-2, respectively, when the masking earphone is placed on the appropriate acoustic coupler, ear simulator or artificial ear.
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