Value of a premium Ethernet cable

The part I can agree with is "try it yourself at home"

If you think you are getting noise into your analog system via the Ethernet, I suggest you have a crappy Ethernet NIC so you are expecting magic cables to fix a bad design.  If you tested you would probably find a lot more garbage is from the processors in the router and switches and not RFI. If your receiving device does not take care of it, it was not correctly designed to work in the intended environment. Blame your box, not the cable.  As far as which cable it is possible to transfer this noise, it is only the last link as the signal is reconstructed in the router and any switch. 

If you believe, so be it. 

What you hear is what your brain says, not the actual sound.  -140dB noise flor? Well that is truly fantastic so quite a great system. Not sure how you get that as even a Bryston amp has about a 114 dB SNR. -140 is pushing Johnson noise. With what source material? A CD with 110 dB dynamic range compressed to maybe 40 to make it loud?   A super great LP direct to disk that maybe has 65dB?  Or do you have some first generation  24/192  digital files before mastering?  I bet what you are actually hearing is more like -80 dB if it is actual physical, not perceived. 

Oh, yea, guess I'd agree a lot of big box cables and hubs are junk. So junky I only get 360 Mbs on my computer with Amazon cable, self terminations, Netgear dumb hubs and the supplied Spectrum router and Modem.    Not saying Belden is the only or the best but if you buy their wire, it will meet spec.  I have had no problems with Netgear hubs.  Instead of expensive linear supplies, I just put a ferrite on the wall wart cable. 

@tvrgeek

If you think you are getting noise into your analog system via the Ethernet, I suggest you have a crappy Ethernet NIC so you are expecting magic cables to fix a bad design.

I’m sure I was getting noise from my Panoramic modem that the streamer is plugged into directly.

The magic Ethernet cable cost $130, came with a 60 day no questions asked return policy and absolutely sounded better than the $20 Belden cable.

No placebo effect, and my bias was in fact against the magic cable - I wanted to send it back.

Tomorrow I will be trying out a black-magic Ethernet cable to compare with the magic cable, also returnable.

Either way this was a low cost solution that didn’t require another powered device that I have no room and no spare outlets for.

Yes, there is abundance of snake oil in this industry but there are also plenty of really effective reasonably priced products.

@macg19 try giving a value Amazon optical set up a try.  Under $100 without LPS. Couple hundred with an LPS. Some like it others don’t and it’s returnable.  Worked wonders for me. Set up is  router-ethernet cable- FMC-Optical cable- 2nd Fmc - best ethernet cable- streamer. 

FMC Need 2: https://www.amazon.com/gp/product/B0716XT1QT/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1  

Optical cable Need 1:

https://www.amazon.com/gp/product/B08PTTWT1F/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
LPS Optional but worth it , powers 2 FMC’s need 2 cords.  

https://www.amazon.com/gp/product/B07T44S4MV/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

So far, no one has alluded on which type of Ethernet cable is better than others for high end audio.

Jussi Laako - the owner of Signalyst (HQPlayer - a product that I like) has done a lot of research on the pre-DAC part of the signal and signal transfer.

He recommends using CAT6 / 6A U/UTP (plastic connector ends. No shielded cables like STP or F/FTP).

No one has eluded because in truth, CAT-3 is more than what is needed.  This is just another "reaching for magic" topic by well meaning folks who do not understand how Ethernet works.  That extends to a lot of equipment makers apparently. 

Cost has come down, so no harm in running 6a if it makes you feel good and future proofs you.