Kuk F K, Harper T, Doubek K
Department of Otolaryngology-Head and Neck Surgery, University of Illinois at Chicago 60612.
J Am Acad Audiol. 1994 Mar;5(2):99-109.
In the present study, we measured preferred real-ear insertion gain (REIG) under different levels of speech and noise to assess whether current automatic gain control (AGC) and automatic signal processing (ASP) hearing aids are operating optimally. Preferred REIG for optimal speech clarity was determined under seven speech and noise conditions. In four conditions, speech (discourse passages) was varied from 55 dB SPL to 85 dB SPL in 10-dB steps at a fixed signal-to-noise ratio (S/N) of +5. In the remaining conditions, speech was fixed at 65 dB SPL while the noise level was varied in 5-dB steps to yield S/Ns from +10 to -5. The results showed that subjects selected less gain as speech or noise levels were increased. In general, less overall gain was selected as speech level was increased, and less overall gain, especially in the low-frequency region, was selected as the S/N ratio became progressively poorer. These results are discussed in relation to how hearing aids with adaptive frequency/gain responses should respond to varying input levels to achieve optimal clarity of speech.
在本研究中，我们测量了在不同语音和噪声水平下的偏好真耳插入增益（REIG），以评估当前的自动增益控制（AGC）和自动信号处理（ASP）助听器是否处于最佳工作状态。在七种语音和噪声条件下确定了实现最佳语音清晰度的偏好REIG。在四种条件下，语音（语篇段落）在固定信噪比（S/N）为+5的情况下，以10 dB步长从55 dB SPL变化到85 dB SPL。在其余条件下，语音固定在65 dB SPL，同时噪声水平以5 dB步长变化，以产生从+10到-5的信噪比。结果表明，随着语音或噪声水平的增加，受试者选择的增益减少。一般来说，随着语音水平的增加，选择的总增益减少，并且随着信噪比逐渐变差，选择的总增益减少，尤其是在低频区域。结合具有自适应频率/增益响应的助听器应如何响应变化的输入水平以实现最佳语音清晰度对这些结果进行了讨论。
