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被你引来引去的文章,看人家的结论:
6 n; I- b; a* P' @" T+ _. ~Obviously, the cable is just a pair of wires below the transition frequency, and your speaker cables (regardless of claims or cost) are exactly the same. In case you may want to simulate this effect yourself, I used DCR=1Ω, L=200nH and C=100pF per metre, and used a 100 metre line. A shorter line does exactly the same thing, but the frequency where it becomes a transmission line (rather than a couple of wires) increases as the line length is reduced. For a 10 metre cable, the frequency is 1Mhz, and for 3 metres this increases further to 3.3MHz. These effects were present in all the previous simulations, but were masked by the amplifier's rolloff.1 c6 \0 x2 \' J9 d% |7 z3 G! l
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不管是同轴电缆还是你的音箱线,即便是以他用来计算的放得很大的模拟参数DCR=1Ω, L=200nH and C=100pF per metre,10米的线在1Mhz的频率以下都可以认为是理想传输线,3米的极限是3.3Mhz。, g4 a; F' g0 s7 B* ^; e- X4 g. \
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* Z5 F1 C; G( ]( D) dIt is worth noting that none of these cables is 1dB down on midband level at any frequency up to 20kHz, and even the Figure-8 lead is only 1dB down at 50kHz - it is a rare tweeter indeed that will be anywhere near as good, regardless of price
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即便是五金店卖的8号线,在50khz也不过是1db的衰减。
" p' f( G- L0 U3 s7 g注意了,人家比的是图21里红绿线的差值。
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! A) B" C! `% Y, and the Goertz cable will set you back about US$200 a pair for 4 metre lengths (and maybe make your amplifier oscillate). Naturally, you can spend a great deal more (and still make the amp oscillate), but I don't see much point.
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由于它过大的电容,200美刀一对的好线可能会引起放大器反馈振荡(应该是这意思吧),尽管它在超出20k以上的频段取得了很好的频响拟合,但作者还是看不出它可取之处。 |
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