A question I have been pondering. If USB and I2s both do 384k Why do I see suggestions about using AES or something else? Am I missing something? Why would you not want the best connection or once again am I missing something?
And if this is in the wrong area can it be moved.
In my setup, I personally prefer SPDIF over USB.
Some servers and DACs are optimized for specific output/inputs.
Ok . I guess in my limited experience my Main is best with USB or I2S (Rockna Wavelight) all my other Dac’s as well.
Personally have love / hate relationship with USB. With some equipment when the implementation is good it works well but requires finding a good cable. Other times it introduces noise from components.
I have found AES, BNC, SPDIF less picky, less prone to inducing noise and easier to simply get a nice sound character out of.but that’s just me and my older ears. 
and also because very little (prob < 1%) of the music I play locally or have access to streaming is greater than 192 kHz.
Even though I am probably older…Haha!
Granted. 90% of what I listen to as well but I see so many recs for AES or spdif so I was curious.
The main benefit to AES or SPDIF is that there are a lot of known good components out there designed to reclock USB and output those sources. AES and SPDI carry their own clocking signal and thus the DAC doesn’t have to work to decode that and often the external clock used is of much greater quality and implementation than the DAC. So there is often a lot of gain.
Depending on the DAC and it’s implementation, it can cound much better with a good AES or SPDIF input. Some DAC have phenomenal USB implementations and can sound great or even better than a an external signal coming in with inferior timing already encoded. It varies a lot but generally a goood DACs do better with USB. Some manufactures though eschew USB altogether like Berkely Alpha Ref. line.
Thank you for that.
Personally have love / hate relationship with USB. With some equipment when the implementation is good it works well but requires finding a good cable. Other times it introduces noise from components.
I have found AES, BNC, SPDIF less picky,
Agree with this. My streamer+dac sees each other as a device via USB, such that if I turn off the DAC before turning off Roon it would actually have issues on the next listening session. And then some USB cables +/-5V have issues, etc.
Not everything has I2s, and better there is no standard.
AES/I2s vs USB is the difference between clock provided by the streamer and clock provided by the USB interface on the DAC, so YMMV there, depending on the source some DAC’s will sound better recovering the clock from the AES signal, and some will have a better internal clock on the USB converter.
Most people also don’t need more than the 192K AES provides, I personally do have a couple of DSD256 tracks that won’t play over AES, but it’s very rare and they are probably just upsampled rather than mastered at that rate.
I personally preferred the Pacific via USB from the Optical Rendu vs AES from the NS1, but it was a very close call and the additional format support was a part of the deciding factor.
All of this is helpful and also why I lurk here, I learn something new ! My Roon Nucleus which is Linux based feeds my Rockna via USB and then from the Rockna out to my amps. No Noise that I can hear at all. Then again my old ears may not be 20/20 so to speak.
The problem when we talk about noise is for the most part you don’t hear noise, you hear the change in presentation when it’s not present.
But I wouldn’t overthink it.
I suppose I did not consider that.
I want to be clear, when i say NOISE, i mean actual NOISE, and usually related to hearing the inside of a component ie. DAC, PC, streamer, whatever is behind the USB. I have had this actual problem several times throughout the years on various components.
You are also 100% correct though in changes in the presentation, much agreed with you there sir.
I personally have never had an in issue w/ an AES or SPDIF output or cable allowing internal electronics “noise, ticks, clicks, pops etc” through. . This has been my personal experience so i just wanted to add that clarification.
One other thing regarding AES is that it has a dedicated ground, and it’s higher impedance than standard digital coaxial (110 Ohm vs 75 Ohm).
I’ve only used AES a handful of times, but that dedicated ground seems to be the difference (noise being ameliorated).
I always use the computer monitor analogy. You can go for a year without cleaning the screen of your monitor. Then one day you clean it and go WOW. That’s what moving your USB out of your Roon Nucleus and going through some intermediary noise and signal cleaning device like a USB reclocker (aka DDC) before your Rockna.
It doesn’t even take a tremendous outlay. Singxer SU-1 Kitsune Tuned Edition DDC ***SALE PENDING For Sale - US Audio Mart Something like this would probably let you see what it’s all about.
I have my Denafrips Iris and that has I2s to feed the Rockna. I just do not have it inline at this particular point,
Oh, then you’re set. Let us know what you think we you do bring it online. Any output would far surpass your current direct to the DAC approach.