If you stream music from the internet, I can't recommend this more highly


I had been using a Roon Nucleus to stream Qobuz, with my Chord Qutest directly connected to the Nucleus. I thought I was getting pretty decent sound quality. And then I got a marketing email from Small Green Computer touting some of their optical gear. The basic idea is that normal cables and connections used to stream from the internet pick up noise of one kind or another (radio frequencies and electromagnetic something or other). But fiber optic cables and their connections/interfaces do not. I don’t know anything about anything, but it made theoretical sense to me, it wasn’t a huge amount of money ($1,400), and with a 30 day return policy I figured I could always return it if I didn’t hear any improvement. Well, I didn’t just hear a slight improvement; it was like turning on the lights in a dark room. Much greater clarity and detail, much better micro and macro dynamics, better timbre to acoustic instruments -- overall just more lifelike. Two quick examples: I’ve listened to some of Steely Dan’s top songs 100s of times over the course of my life, and this is the first time I’d ever noticed a particular and very subtle sound characteristic of Fagen’s keyboard in Babylon Sister. It’s hard to describe, but it’s like there’s a slight sound of air being exhaled by it. The other example: the specific timbre of whatever percussive instrument is used at the beginning of Copeland’s "Fanfare for the Common Man" (a recording by the Minnesota Orchestra). There’s more of a metallic sound than a drum skin sound to it that I didn’t know was there before. The metallic sound starts in the center and then projects out and to the sides, like a wave washing over you. Anyway, I’m just thrilled about having stumbled upon the whole "optical" thing and felt obligated to let others know about it. If you stream music over the internet, I highly recommend giving it a try. (The product I got was the opticalRendu, with the linear power supply option, and the Fiber Ethernet Converter Bundle option.)
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The opticalRendu is a streamer you attach to a USB DAC. Some DACs have build in streamers but most don’t.

The Rendu takes music from Ethernet and sends it down the USB cable to the DAC. For the DAC to sound its best this USB signal needs to be free of noise and jitter.

So I’m just not sure how "cleaner" ethernet packets going into a devices memory chips (cache) would improve the sound.

We are not "cleaning" ethernet packets. There are digital and work the same if analog noise is present or not. We are remoting the analog noise from the Ethernet cable and keeping out of the analog stage of your DAC.


Any competent DAC will filter the noise on the input then buffer the frames before it is sent into the conversion. It's simple to test these claims if you have the right equipment, measure the output of the DAC with the device and without see if the measurements vary enough to be audible. 
I have a "competent" DAC - the Chord Qutest.  I originally had it connected directly to my Roon Nucleus.  When I added the optical gear, it dramatically improved the sound.  The difference is not subtle.  I can hear your rebuttal already:  it's all in my head, it's confirmation bias, etc.  Wrong.  I've tried other pieces of gear expecting that they would improve the sound quality, and yet I heard no improvement and was disappointed.  Other pieces of gear, I immediately heard an improvement.  Two other people who posted above heard a clear improvement as well, one of which wrote a review about it:  https://www.dagogo.com/audio-blast-sonore-systemoptique-signature-rendu-se/ 

By the way, anyone can try it out for themselves with no risk -- they offer a 30-day, no questions asked return policy.  Then they'll know whose word they can trust.
You might have a competent DAC but your test process for determining differences is nonexistent. 
My test process was the one that matters most in this hobby:  actually listening.  You on the other hand haven't even done that, and yet you're going to make a judgment based on some universal (and btw, untested) theoretical assumption about all "competent" DACs.