20db
例句释义:1.In areas with good reception, its easy to maintain four or five bars of service, because a loss of 20dB will barely register onscreen.在接收好的地方，很容易保持4到5格的信号格，因为20dB的信号减少几乎不会体现在屏幕上。
2.Benefited from the new structural design, noise can be controlled ultra-quiet at 20dB status.得益于全新的结构设计，噪音方面可以控制在20DB的超静音状态。