|
被你引来引去的文章,看人家的结论:
% ?. u3 d$ J( e, e- EObviously, 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.
5 l- g+ Q4 e9 l/ H
' F$ o# _! n# k7 W! T; \8 i" Y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。2 L, O* l" D' L+ r
% K) i) m7 A: I4 M
7 [/ N% C# r& \. K; W/ c/ F
It 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! h, j$ U/ b z/ M v) T) L
( O3 @" d7 {6 Y2 l
即便是五金店卖的8号线,在50khz也不过是1db的衰减。
. p8 S- B6 I* C* N注意了,人家比的是图21里红绿线的差值。
6 I) Z. ^/ d. H }9 e
+ k# p4 x7 o4 K, s, and the Goertz cable will set you back about US$200 a pair for 4 metre lengths (and maybe make your amplifier oscillate). Naturally, you can spend a great deal more (and still make the amp oscillate), but I don't see much point.. e8 W0 g! I4 e. r
% B2 Z P N. P! j$ N m y& O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。 |
|