Is optical mostly a waste of time versus Ethernet?

Eno between server and renderer would be interesting

I tried that today - Ethernet from router to switch (located near router) then 45 feet from switch to GigaFOILv4 (located near the server) then short Ethernet to server and short Ethernet from server to ENO then captive Ethernet from ENO into Metrum Ambre renderer.  AES/EBU XLR cable from the Ambre into the Mystique EVO B4B21 DAC.  

Simple without the fiber converters and accompanying power supplies.  It sounds really good.  I don't know why exactly but the sound was full, rich, and musical with a wide range of music from Coltrane to Chili Peppers.  I want to next compare this to the same set-up into the server, but then running a USB cable from the USB output of the server directly into the USB input of the DAC, without using a separate renderer.    

@mitch2 I’m envisioning Stockhausen’s WDR Studio;

https://120years.net/wordpress/wdr-electronic-music-studio-germany-1951/

Fundamental problem with optical is you can’t turn light pulses into music, atleast not yet. It to has at some point be converted back into an electronic/ Ethernet signal whether it be with converters outside the streamer or like lumin or other devices that accept a direct fibre, the conversion happens inside the streamer. Obviously if you leave until your inside the streamer, you have no opportunity to intervene to remove this noise. As with any powered device on the network the optical to electronic conversion is likely to create and emit high frequency noise, which left untreated will have a detrimental effect on the performance of the streamer and the onward da conversion. Powered devices like the gigafoil might well clean what’s going in but they will likely add noise in their conversion process to the signal they transmit,  Passive filtering as it stands is the only effective solution as it stands.

@teknorob23 who makes passive filters other than Network Acoustics?

There are several power supplies in most people's digital signal chain, including those powering the modem, the router, and any switches, as well as power supplies inside of the servers and DACs that process the digital signal.  Ethernet itself is galvanically isolated but some believe that optical isolation near the endpoint can improve on that wrt noise reduction, which is probably where the idea of using fiber came from.  The Network Acoustics stuff is unpowered and isolates using transformers, which do not break the electrical connection the same as optical.  My Gigafoilv4 is powered by an HDPlex LPS so there are no switching supplies in the chain following the optical isolation offered by the Gigafoilv4.  Using the ENO just before the Ambre endpoint sounded good yesterday so if I switch to using USB directly from the server to DAC, I may try using only the ENO just before the server, and no other boxes needing power supplies.  I guess you just need to try stuff and listen.