|
|
被你引来引去的文章，看人家的结论：! {" k; ^5 _) ~0 e# s5 D9 K' j
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.
# p+ r5 i M4 |7 ~: p3 ]( f
5 ~) h9 s( c5 t# O/ k" o4 ?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。
* H4 r' q) @2 L0 j8 P* z
7 N% Z" ^4 h2 ^9 V8 ]" I7 l! \" k/ m2 W2 o1 d' v
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, n* C- _$ d3 N5 ?) b1 d6 c
" W- {5 m0 G9 \! h9 U- h( [
即便是五金店卖的8号线，在50khz也不过是1db的衰减。
& B- l4 a* N! h+ v9 c6 ^注意了，人家比的是图21里红绿线的差值。& f: _& T1 }/ u5 q. Y
0 p8 |- ]. e1 k4 V' ~4 G. M, 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.( ^+ t2 t/ u) W' a7 e6 x
, [5 f8 u0 X- q. O s5 E5 [. {
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。 |
|
IP卡
狗仔卡
发表于 2010-1-15 14:26
显身卡
