本帖最后由 中关村东路 于 2021-5-13 15:30 编辑
有意思,家里坏了两根网线我也正想买呢,看到如下三个链接,建议使用非屏蔽线,你测试的似乎都是屏蔽线,试试对比下不屏蔽的六类?
链接一是dcs论坛上一个dCS: Programme Manager的说法,
https://dcs.community/t/what-ethernet-cable-are-you-using-into-you-streamer/882/23
Andrew Papanikolas, dCS: Programme Manager, Streaming Audio, Apr '20
I use an Amazon Special CAT6 (I believe the brand is either Cables 2 Go or Cables Matter) between my Vivaldi Upsampler and Ubiquiti switch.
I have a unique position in the industry as the “network streaming guy” for one of the premier digital audio manufacturers so I could easily have any audiophile cable currently available. I still chose the basic unshielded cable that passed certification.
Keywords above are unshielded and passed certification.
链接二解释的比较详细,
https://audiophilestyle.com/forums/topic/46225-shielded-vs-unshielded-ethernet-and-grounding/
The issue with shielded Ethernet is that the shield has the potential to connect the ground plane of the audio device to the ground plane of whatever it's connected to. This gets especially bad with switches that use a wall wart power supply as they do not have a real connection to earth. In that case the audio component's ground becomes the ground for the network device and potentially anything else connected through that network device. It gets ugly from a noise perspective.
......
We recommend against using shielded Ethernet cables as the shield is a very easy way for noise to get onto the ground plane of the audio system. This is especially bad when dealing with digital as that noise can create some issues both on the digital and analog sides. The noise may not be audible, but it's definitely within the current differential between a couple of bits. In other words, you may not be able to hear it, but it may be messing with the overall resolution of your system.
链接三是朋友发给我的,似乎是山泽的解释
https://www.sohu.com/a/336783119_120150037
2、屏蔽网线对布线系统的要求 我们对屏蔽网线存在一个很大的误区:只要选择屏蔽网线来进行网络布线,肯定会大幅度的屏蔽各种干扰。 其实屏蔽网线对布线系统的要求很苛刻,首先需要布线场景有良好的地线系统,通过地线才能将干扰电流导向大地。与此同时,布线系统需要处处屏蔽,比如水晶头、插座、交换机等等,如果有一个部件不是屏蔽的,整个系统就起不到屏蔽效果。而目前市场上还很少有可支持屏蔽的网络集线器或计算机,所以很难实现整个传输链路的屏蔽。 3、屏蔽的真相 我们要知道屏蔽网线抵抗的是来自外部的干扰,也就是说外部环境有强干扰时,才适合使用屏蔽网线,比如网吧、机房等网线较多的环境。对于网线内部的信号串扰是没有任何降低作用的,相反如果屏蔽网线高频传输时,需要两端接地,但是接地的两端很容易出现电位差,这样一来,屏蔽层会产生干扰电流,成为系统中最大的干扰源。
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