notch noise 残余噪声
And it turns out that my left ear’s hearing is noticeably weaker in certain frequencies—it has what ear docs call the “noise notch” that afflicts those exposed to serious sound.
原来我的左耳对某些频率的声音特别不敏感——这就是医生们所说的“噪音空隙”，它们困扰着那些在噪声下工作过的人们。
Notch filter for external noise suppression.
陷波滤波器外部噪音抑制。
On the right side is the Micro SIM slot and another notch in the band at the bottom, and up top there's the power / sleep button, headphone jack, another notch, and new noise-canceling microphone.
另一边是 Micro SIM 插槽和位于底部金属带中的缺口。 顶端是电话和休眠按钮，耳机插口和另外一个缺口，以及新的降噪音麦克风。
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