Frank T, Richter U
Ear Hear. 1985 Jul-Aug;6(4):206-10. doi: 10.1097/00003446-198507000-00007.
This research determined the influence of temperature on the output of two Bruel and Kjaer 4930 mechanical couplers using a Radioear B-71, B-72, and a Pracitronic KH 70 bone vibrator. When the temperature of the mechanical couplers was varied from 17 degrees C (62.6 degrees F) to 29 degrees C (84.2 degrees F) in steps of 3 degrees C (5.4 degrees F) and the bone vibrators had a constant temperature, the output of each mechanical coupler systematically decreased as its temperature increased for each bone vibrator type. The largest output differences for both couplers and each vibrator occurred at 4000 Hz. The average of these differences across the couplers and vibrators was 6.6 dB higher at 17 degrees C than at 29 degrees C which dB/3.6 degrees F). When the temperature of the bone vibrators was 17 and 29 degrees C and the mechanical couplers were maintained at a constant temperature, there were little or no differences in the output of the mechanical couplers. The temperature of a mechanical coupler rather than that of the bone vibrator is a critical variable in bone conduction calibration. Mechanical coupler temperature-dependent output coefficients were determined for use in bone conduction calibration from 250 to 4000 Hz for all three bone vibrator types and at 6000 and 8000 Hz for the KH 70.
本研究使用Radioear B - 71、B - 72和Pracitronic KH 70骨振动器，确定了温度对两个Bruel和Kjaer 4930机械耦合器输出的影响。当机械耦合器的温度以3摄氏度（5.4华氏度）的步长从17摄氏度（62.6华氏度）变化到29摄氏度（84.2华氏度），且骨振动器保持恒定温度时，对于每种骨振动器类型，每个机械耦合器的输出随着其温度升高而系统性降低。两个耦合器和每个振动器的最大输出差异出现在4000赫兹处。在17摄氏度时，耦合器和振动器的这些差异的平均值比在29摄氏度时高6.6分贝（相当于1.83分贝/华氏度）。当骨振动器的温度为17摄氏度和29摄氏度，且机械耦合器保持恒定温度时，机械耦合器的输出几乎没有差异。在骨传导校准中，机械耦合器的温度而非骨振动器的温度是一个关键变量。针对所有三种骨振动器类型，确定了从250到4000赫兹以及针对KH 70在6000和8000赫兹时用于骨传导校准的与机械耦合器温度相关的输出系数。
