I should have mentioned that I read the entire Ethernet Throttle thread and the blog article that introduced the major milestone. And I’ve read many of the articles on measurements of Ethernet equipment. Just trying to collect data 🙂
If the goal is to attenuate common-mode interference over the broadest possible band,
many turns could be disadvantageous.
Yes. With very low cost clip-on ferrites, there’s no reason not to cover the entire length of a cable. This also solves the problems caused by mismatched impedances at the ends of the cable. I have 300 or more ferrites deployed across 6 power cables and two BNC cables.
The other is the impedance for the common mode , which is generated by ferrites or chokes, as in the video. In my opinion, the increase in interference in the video is caused by interference being reflected from the monitor. It would be interesting to take a measurement by attaching ferrites to both ends directly in front of the monitor, i.e. between the monitor and the first ferrites. In my opinion, you will then see the same increase here, as the interference is now reflected here. But that is all just speculation.
I’m unsure what you’re saying here. At the end of the video he attached a ferrite at the end of the cable closest to the monitor. Are you referring to the ferrites that are built-in to the cable and the placement of the clip-on ferrite with respect to the position of the built-in ferrite?
Anyhow, I believe you have the equipment to perform detailed measurements and listening tests with unbalanced versus balanced impedances along the length of a cable. A key reason for my efforts to post on this forum is that you have the measurement equipment, which is rare.
The solutions are really interesting and the owner seems to know what he’s doing. Thank you for the link. However, I wonder why you convert USB to SPDIF and then to optical and not just use Toslink? But here you have the timing problem again. It’s also interesting that he prefers the Mojo2 to the Dave.
TOSLINK limits sample rates to 192KHz, which is perfectly fine for streaming. Many people, including him, use software like PGGB or HQ Player to do upsampling to 768KHz (or even higher). With Chord DACs the highest sample rate accepted is 768KHz. Since this won’t go over TOSLINK, the alternative is the convoluted path. With Chord DACs dual-SPDIF enables 768KHz – I’m not aware of any other DACs that support this data rate over dual-BNCs (certainly not dCS, the company that created the dual-BNC SPDIF standard), so this convoluted path is specific to Chord DACs.
I’m mildly sceptical about his preference for Mojo 2 versus DAVE simply because the final noise shaper and PWM stage have vastly better transparency in DAVE. But there are some mathematical refinements that Rob Watts introduced with Mojo 2 that mean its volume control is better, in theory…
That’s a really cool solution – I need a CNC milling machine
He paid a company to construct the case for him, using designs that he submitted 🙂
Regarding the galvanic isolation with USB, I still think the artistic fidelity AFI + USB solution from Ralf Koschnike is top: https://kopfhoererboutique.com/products/artistic-fidelity-afi-usb-modul?variant=14147847946285
Two optical cables are used here. As far as I understand, the signal is transported on one cable and the clock on the other, so there are no timing problems.
I use this USB to TOSLINK convertor to connect a mini-PC to my hi-fi for things like YouTube:
https://www.amazon.co.uk/dp/B0B2DBGKL3
I suspect that different frequency ranges of RF noise have specific effects on sound quality. I wrote a fairly long list of the different sound quality problems caused by RF noise here:
https://www.head-fi.org/threads/chord-electronics-dave.766517/page-1113#post-16160284
Jawed