Help me understand better solutions for ethernet

Given your circumstances wifi is likely the right answer. Just use a quality ethernet cable between the bridge and repeater. I hope you are hopping along again!

Update - I blew my knee out because of an ice storm two weeks after I posted here. As such, I’ve had plenty of time to listen and A/B. The A/B testing was three identical songs in the same format via:
1. Internal HD of my Aurender.
2. Streamed via Tidal (non MQA) via ethernet Cat 7
3. Streamed via Tidal (non MQA) via wireless

My assumption at the beginning was direct from Aurender would be best, followed by hardwired Cat 7 with wireless pulling up the rear. Well, long story short I was wrong. Wireless won every time. Not by a huge margin but enough to consistently be picked as "best" seeming to give faster attack and fuller bloom. This was repeated several times on different days and with friends who’s ears I trust.

With only a .5 meter run of ethernet cable at this point, I’m not sure additional items in the chain such as a Eno would be helpful. Maybe a better shielded ethernet cord?

Disclaimer: I live on top of a mtn in the middle of nowhere so very little to interfere however the ATT tower is a stones throw so the wireless signal is as close as possible. So your mileage may very dramatically if you’re a city dweller.

I have been experimenting on how to get the best sound quality for streamed music to my Innuos Zenith Mk3: in my setup inserting an EMO EN70-HD galvanic isolator into my ethernet cable and connecting from there with a 10in Meicord cable to the streamer yielded the best result. I also use a short Meicord cable to connect the router to the ethernet. Solutions over Wifi (Apple Airport Extreme in bridge mode) have sounded equally good at times but are inconsistent depending on network load.

Well it took a 1.5 hour visit from my internet provider/IT tech guy (he arrived on 20 mins notice at 8:30 pm on a Saturday night while snowing = amazing customer service!) to setup my TP Link access point. What should have been an easy 5 min install by me turned into anything but.
Tomorrow when I have some time off I'll A/B simple wired CAT 7 vs. wireless. I'm not sure there will be much difference only because my internet comes to me wireless via an ATT tower here on the mountain. Currently no one out here has a hard fiber line except the govt, who has five separate independent lines but their not sharing...  From there will continue deeper down the rabbit hole as you say.

ENO works.

So does the Etherregen

I run fiber but never really listened for benefit-it helps me sleep at night not worrying,
 but I think I have the wrong SFP modules, so waiting for modules and cable from Sonore.  will test for benefit soon

Added a clock to the Etherregen and LPS- both helped, the clock more
also have SOtM cDBL CAT7w/filter-definitely better than standard ethernet cable

it's a very deep rabbit hole but worth exploring

Thank you all for thanking the time to reply.

I think the best route is to order up versions of all three solutions and test/listen. Most come with 30 day trials so can't lose. 

Latitk - I will certainly add Eno to the list as I do like the passive route.

Arch2 - I have just received a TP Link access point that Upscale audio recommends but it's giving me fits trying to setup in client mode. I agree for $25 if it sucks I can use it elsewhere around the house. 

Jond - You'd think the rural setting would be a huge plus, but living 3 miles from a top secret underground military facility who knows what's floating around out there. Stranger Things playing out in my backyard. LOL.

I had 75’ of Ethernet from the router to the stereo room which went to the bridge of my PS Audio Directstream Jr. I never thought anything of it and in fact I always assumed an Ethernet connection was better than WiFi. The DSJ has no WiFi capabilities. Like you, I started reading about noise in a hardwired Ethernet connection and decided to try a WiFi repeater that has an Ethernet port. So basically I program this WiFi repeater to connect to my existing WiFi then plug the Ethernet from the DSJ into the repeater. I was stunned at the difference between Ethernet and WiFi in my application. I’m definitely hearing deeper into the recordings, plus it was dirt cheap. I spent 50 bucks on a Linksys. You can get something like that from bestbuy and give it a shot and see if it helps in your application. If not, take it back. Best of luck.

Based on my experience,

1. Ethernet switch does not completely eliminate noise. All Ethernet switches generate / add noise to the signal, it’s just a matter of to what degree,

2. Conversion to optical defeat the purpose if you’re adding a conversion box...plus optical strips away dynamics (think of dry and thin audio),

3. WiFi vs Wired...audio quality great depends on surrounding electronics, interferences and the streamer itself. Again, wired sounds better in almost every instance. WiFi adds convenience and good for casual listening environment.

The system like yours (which is excellent) deserves a wired Ethernet connectivity. I also own Aurender (N10) and recently added a ENO Filter between my router and N10. The uptick in SQ was far from subtle. You don’t realize the noise level until you insert a device like ENO. It’s a passive device so no shelf space needed and no external power supply mess.

https://www.networkacoustics.com/product/eno-streaming-system-995-incl-vat/

Also check out this thread on fiber optic connectivity with Lumin, 

https://forum.audiogon.com/discussions/fiber-cable-instead-of-ethernet-cable

mcslipp I would think living in a rural area on top of a mountain that you likely face fewer extraneous noise issues than a lot of us.  I noticed, in a noise rich urban environment, a very slight improvement moving to a better shielded, though non-audiophile, Cat8 ethernet cable. I find a wired connection to also sound slightly better though it's a subtle difference. I've been curious about those swtiches also but have yet to try one.

Run a quality shielded Ethernet cable

My ACTUAL experience is that it’s not a problem. I run Ethernet from a TP-Link managed switch through wall cavities to my streamer. I put an EMO Ethernet filter in the line -- no audible difference. (I kept it for its surge protection.) I’ve also compared WiFi to Ethernet (on the Auralic Aries G1) and found no audible difference.

I’ve moved my speakers 6 inches -- difference! Added acoustic treatment -- difference! But Ethernet tweaking, IMAE, has not proved of any value.