Medizinische Physik and Cluster of Excellence "Hearing4all," University of Oldenburg, Küpkersweg 74, 26129 Oldenburg, Germany.
J Acoust Soc Am. 2018 Oct;144(4):2072. doi: 10.1121/1.5056173.
Spatial hearing abilities with hearing devices ultimately depend on how well acoustic directional cues are captured by the microphone(s) of the device. A comprehensive objective evaluation of monaural spectral directional cues captured at 9 microphone locations integrated in 5 hearing device styles is presented, utilizing a recent database of head-related transfer functions (HRTFs) that includes data from 16 human and 3 artificial ear pairs. Differences between HRTFs to the eardrum and hearing device microphones were assessed by descriptive analyses and quantitative metrics, and compared to differences between individual ears. Directional information exploited for vertical sound localization was evaluated by means of computational models. Directional information at microphone locations inside the pinna is significantly biased and qualitatively poorer compared to locations in the ear canal; behind-the-ear microphones capture almost no directional cues. These errors are expected to impair vertical sound localization, even if the new cues would be optimally mapped to locations. Differences between HRTFs to the eardrum and hearing device microphones are qualitatively different from between-subject differences and can be described as a partial destruction rather than an alteration of relevant cues, although spectral difference metrics produce similar results. Dummy heads do not fully reflect the results with individual subjects.
助听设备的空间听觉能力最终取决于设备麦克风对声线索的捕捉程度。本文利用最新的头部相关传递函数（HRTF）数据库，对 5 种助听设备样式中 9 个麦克风位置集成的单耳频谱声线索进行了综合客观评估，该数据库包括来自 16 个人类和 3 个人工耳朵的数据。通过描述性分析和定量指标评估了鼓膜和助听设备麦克风之间的 HRTF 差异，并与个体耳朵之间的差异进行了比较。通过计算模型评估了用于垂直声音定位的方向性信息。与耳道内的位置相比，耳甲内的麦克风位置的方向性信息存在显著偏差且质量较差；耳后麦克风几乎无法捕捉到任何方向性线索。即使新线索能够被最优地映射到位置，这些误差也可能会损害垂直声音定位。鼓膜和助听设备麦克风之间的 HRTF 差异与个体之间的差异在性质上有所不同，可以被描述为相关线索的部分破坏而不是改变，尽管频谱差异指标产生了相似的结果。假人头并不能完全反映个体受试者的结果。
