What type of masking noise is used for effective speech audiometry?

The use of broad band noise that is filtered to mimic the average spectrum of speech is particularly effective for speech audiometry because it closely resembles the frequency characteristics of human speech. This type of masking noise effectively obscures the speech signal without distorting it, allowing for better assessment of an individual's ability to understand speech in the presence of competing sounds. By matching the spectrum of the noise to the frequencies where speech sounds are prominent, clinicians can create a more realistic testing environment that accurately reflects real-world listening conditions.

This approach is important because speech consists of a range of frequencies, and using a noise type that captures that range enhances the reliability of the audiometric evaluation. The other options, though relevant in different contexts, do not provide the same effective simulation of the speech spectrum needed for accurate results in speech audiometry. For instance, while narrow band noise can target specific frequencies, it may not encompass the full range of speech frequencies necessary for this testing. Similarly, white noise is broad and does not accurately reflect the specific characteristics of speech, and a pulsating pure tone focuses on a single frequency, which is not representative of speech sounds overall.