The term ‘multimodal’ typically refers to the combination of two or more sensory modalities; however, through the advancement of technology, modality variations within specific sensory systems are being discovered and compared in regards to physiological perception and response. The ongoing evaluation of air vs bone conduction auditory perception modalities is one such comparison. Despite an increased awareness of the potential benefits of utilizing bone conduction pathways, a complete understanding of the human auditory system, more specifically, the relationship between air conducted and bone conducted sound remains a critical deficiency hindering the development of advanced multimodal auditory displays. Conduction equivalency ratios (CERs), which were defined as the difference in sound intensity levels (in dB) between equally loud signals transmitted in air conduction (AC) (sound field) and bone conduction (BC) modes provided a link between these two modes of hearing by determining the relationship between spectral content of AC and BC sound. The current report aims to describe, in depth, the establishment of such CERs at three BC transducer contact locations on a listener’s head over a range of audible frequencies presented over three signal intensities within a controlled free-field listening environment. Results indicated the AC–BC relationship is not unique and depends on sound intensity, frequency, and BC transducer location. In addition, in terms of head sensitivity, results support similar findings which indicate that the Mastoid and Condyle locations can be considered interchangeable in terms of their frequency-related sensitivity while the Forehead was found to be considerably less sensitive compared to the other locations.

中文翻译：

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空气和骨骼传导声音的多模式听觉等响度比较

术语“多模式”通常是指两种或多种感觉模式的组合。然而，通过技术的进步，人们发现并比较了特定感觉系统内的形态变化，以了解生理感知和反应。空气与骨传导听觉感知方式的持续评估就是这样一种比较。尽管人们越来越认识到利用骨传导途径的潜在益处，但是对人类听觉系统的完整理解，更具体地说，空气传导和骨传导声音之间的关系仍然是阻碍高级多模态听觉显示器发展的关键缺陷。传导当量比（CER），定义为通过空气传导（AC）（声场）和骨骼传导（BC）模式传输的同等响亮信号之间的声强级差异（dB），通过确定两者之间的关系提供了这两种听力模式之间的联系AC和BC声音的频谱含量。本报告旨在深入描述在受控自由场收听环境中，在三种信号强度下呈现的可听频率范围内，在收听者头部的三个BC换能器接触位置处建立此类CER。结果表明，AC-BC关系不是唯一的，并且取决于声音强度，频率和BC换能器的位置。另外，就头部敏感度而言，