实在是耳挂中的王子！
声学。测听设备校准用参照区。第1部分：纯音和耳挂式耳机的参考等效阈声压级。
Acoustics - Reference zero for the calibration of audiometric equipment - Part 1 : reference equivalent threshold sound pressure levels for pure tones and supra-aural earphones.
研究者们顺理成章地得出这样一个结论：当黑板被挂擦时，该声响在我们的耳内放大，加剧了痛苦。
What seems to happen, the researchers reckon, is that when a screech on a chalkboard is generated, the sound is amplified within our ears to painful effect.
应用推荐