有人在音响DIY上撰文, 说用16位(65536级)电子开关,实现了1分贝间隔,96级的音响音量控制, 且是用的 R-2R网络, 此说不正确或不当, 在开始的几级,其衰减分贝是:
1, i= 1, -96 0.32960, -96.32960, 0.000015
2, i= 2, -90 0.30900, -90.30900, 0.000031
3, i= 3, -87 0.21283, -86.78717, 0.000046
4, i= 4, -84 0.28840, -84.28840, 0.000061
5, i= 5, -82 0.35020, -82.35020, 0.000076
6, i= 6, -81 0.23343, -80.76657, 0.000092
7, i= 7, -79 0.42764, -79.42764, 0.000107
8, i= 8, -78 0.26780, -78.26780, 0.000122
9, i= 9, -77 0.24475, -77.24475, 0.000137
10, i= A, -76 0.32960, -76.32960, 0.000153
11, i= C, -75 0.25403, -74.74597, 0.000183
12, i= D, -74 0.05073, -74.05073, 0.000198
13, i= F, -73 0.19223, -72.80777, 0.000229
14, i= 10, -72 0.24720, -72.24720, 0.000244
15, i= 12, -71 0.22415, -71.22415, 0.000275
16, i= 15, -70 0.11479, -69.88521, 0.000320
17, i= 17, -69 0.09504, -69.09504, 0.000351
18, i= 1A, -68 0.03013, -68.03013, 0.000397
19, i= 1D, -67 0.08164, -67.08164, 0.000443
只有在-68分贝后,才可实现-1分贝增量的衰减. |