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本帖最后由 karrigan 于 2009-12-31 12:42 编辑
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回复 456# DarthModder
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* a6 ?1 Q2 b& t) H% m等的就是您的数据...这么爽快地反驳很久没有过啦( Q4 @. |+ p* R" a6 |! _! k6 Q
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第一个链接:扬声器阻抗变化,英文全文引用
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A speaker’s impedance changes depending on the frequency of the signal coming from the amplifier. That’s why almost all impedance ratings are “nominal” rather than exact. For instance, an “8 ohm” speaker may exhibit impedance measurements ranging from 3 ohms (or less) to 40 ohms (or more) at different frequencies. Although the relationship isn’t perfect, think of “nominal” as “average” and you’ll be OK. 1 Z! u0 r" ]7 v& ]
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红字我都标出来了,人家打个比方..您还当实测数据了?而且..就算低至3ohm,又如何?看看你下面引用的第二个链接,看看咸菜阻抗到底多少, x( Y2 ^ D: C4 p+ M3 Y
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第二个链接:
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1 电阻11.15 mΩ 电感626.64 nH 电容68.90 pF 12# Zip 3 Z9 R6 M4 Z: }2 G
2 电阻14.57 mΩ 电感219.82 nH 电容114.83 pF Jon Risch
9 m' k8 M& \9 N1 c5 u( B& [, L3 电阻14.44 mΩ 电感32.81 nH 电容1640.42 pF Goertz MI 1 * }, P) }- z$ }
Table 2 - Simulated Cable Parameters (per metre)
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All values are per metre of cable length, and the simulations were performed using a 4 metre length (a little over 13 feet), as this is fairly typical of most domestic installations. As cables are made longer, the effects described occur at lower frequencies.
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看看红色的单位..电阻0.01几欧姆...4米的线乘以4,正好反驳了您前面咸菜阻抗能大到0.几欧,能够影响到反电动势为输入量的系统吗?第一个链接里面人家打的比方至少还3个ohm呢,差多少倍?
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3 l4 z, c4 L7 k$ J$ p) h第二:电感量,更搞笑了,“高达”627nh,您不看单位的?“nh”,十的负九次方...最大给个20khz的信号又如何?0.01254欧的虚轴分量,比电阻还小,20hz的信号,感抗再除1000,分频器里面电阻多少?电容多少?每米最大感抗0.012欧,阻抗0.014欧的咸菜,还能影响系统的阻尼?更别说那电容了..pf级别的... r, j0 p/ y4 |7 A" M
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没有实测数据?我的数据编出来的?1hz到25hz频段里,哪里体现出趋肤效应了?哪里体现出感抗和容抗的作用了?照您的倍率说法,都差了20倍了,取个对数都差一个分贝啦..依然没有任何体现,衰减幅度完全一样的0.9912,体现了什么...
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最后,感抗和频率成正比,容抗也和频率成正比?您真的学过模电吗?容抗和频率成反比好不好?频率越高,感抗越大,容抗越小 |
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