I am learning here so bear with me please – define “Ethernet lines”.
SEE
alternative explanation - every ethernet port you see, on a switch, on a computer, wherever, has transformer isolation, it’s built right into the receiver chips 
Edit - someone is bound to now tell me of edge cases where this is not true 
So then the purported benefit of galvanic isolation of Ethernet feeds is a myth, right?
What’s the point if the noise source(s) is already isolated?
Again, looking for understanding - not trolling.
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I’ve asked that very question and never received an answer that justified additional galvanic isolation beyond what is already inherent in every ethernet interface.
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I would tend to agree with both of you.
The various ethernet “audiophile” isolation strategies will probably change the level of noise getting through the transformer isolation (noise is AC so will cross the transformer boundary to varying degrees), so may have an impact on sound coming from the DAC, but only in a second hand way - streaming is buffered at packet and protocol level, so will depend just as much, or maybe a lot more, on how well the packets are assembled into a stream once they have arrived at their destination.
All of this is so very implementation specific that everyone will have different results. Hence, if you can easily afford it, it is possibly worth a try, but I can’t help thinking there are better areas to invest in the majority of cases.
It’s 6 am - definitely time for bed
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Well, armed with this new (to me) information, I have to wonder if it is a matter of effectiveness/degree.
Perhaps the inherent design is not 100% effective at isolating (all of) this type of noise.
Another thing for me to explore, I guess. Fortunately (or unfortunately), I have taken steps to minimize the introduction/propagation of this type of noise and it would be relatively easy enough to subjectivity evaluate my music network’s benefit from same by swapping the related kit in and out of the system; and varying the their locations on the signal path.
I’ll add this to my list of things to learn more (and fuss around) about.
Thanks guys.
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It is true ethernet is transformer isolated, yes. What’s unusual about the AirLens is the input AND output are galvanically isolated. So, in most cases, the little computer inside every streamer is spewing its clocks and noise into your DAC via ground and the connection. I don’t know of another device like the AirLens that totally isolates input and output as if it were an island.
The closest any of us might have gotten would be if you had an optical connection to the DAC. That has always been full galvanic isolation. But, alas, we got left with only TOSLINK which is a consumer grade connector that has a lot of other problems like limited sample rates, jitter, etc.
The holy grail would have been an optical cable and advanced transmitter receiver like those that we started working on year ago, the ATT, glass cables. But, sadly, they are not an option.
Thus, the only way to get 100% isolation between in and out is with an AirLens.
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Thanks Paul.
FWIW, at least from my perspective, the recent Q&A here is clearly NOT about the purported benefits of “AirGap” within the pending AirLens.
I, for one, have no reason to doubt the need for, or effectiveness, of such an approach. It’s the kit-to-kit propagation or introduction of noise from Ethernet connection points and along signal paths that I have been inquiring about.
Can’t wait for AirLens to hit the streets…
Good luck with checking off your final punch list items and the roll out.
Cheers.
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Exactly - noise being AC will also cross the transformer to some extent, but ground-wire-bourne stuff won’t.
Paul’s comments about keeping the streamer’s computer-type noise is correct of course (though there has to be some noise etc. from whatever then converts that optical air gapped link back to I2S or whatever?).
Me, I like TOSLINK, despite its limitations, but also still wish a better optical interface was available:
@Paul - are there details available on why the ATT / glass fibre dev work wasn’t practicable?
Edit - this thread suggests cost
So I’m sticking with AES where available and TOSLINK elsewhere (and a bit of RCA SPDIF if necessary).
192 kHz over TOSLINK seems fine (passes bit perfect tests) on every device I have (that understands 192, some of it is 96 max) and is generally followed by reclocking / jitter suppression of one sort or another)
I have recently decided to not bother any more with 384 / 768 as that requires USB and that just feels wrong 
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Also interested in this…seems like a logical next step in evolution of transmission of audio 1s and 0s.
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I’m puzzled by this statement. Every RJ45 jack I’ve ever used had isolation transformers built in on the receive AND transmit lines. 
I’m not PS Audio, but I would be extremely surprised to see DSD128 (as DOP128) via a single SPDIF RCA connection. A 45-ish MHz signalling rate is really asking too much of a connector that was designed for analog audio bandwidth requirements. It would also be the single most demanding signal for the DS DAC FPGA to process.
By comparison, DOP128 via a dual AES-EBU connection (which was designed for high speed signalling) needs only the same 22.5-ish MHz rate that DOP64 requires in single SPDIF. On I2S you get DOP128 for a mere 17-ish MHz or you can go DSD128 native with just 5.664MHz rate on two wires in parallel.
Those two plus USB.
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That’s correct for the RJ45 but since the streamer doesn’t use the RJ45 for anything other than input/communication, now I am the one confused. What’s not clear?
The isolation provided by the AirLens is input (RJ45) and output (coax and I2S).
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Ah, yes, of course also USB to the DS MKII for DSD128. Meant to write, “Other than USB…” Yeah, I am not finding DAC’s via Google that do DSD128 over RCA SPDIF except that there are separate cables per channel. Checking with Bricasti for my neighbour, they recommend using Ethernet for DSD128 to their DACs. So, unless the neighbour switches to the new PS Audio DAC, he would stay with his Antipodes for streaming services, not going to an AirLens. There is no I2S over HDMI input to the Bricasti.
So any indication as to a rough date that this may happen . I’m hanging out to buy one .
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Question, is there some thought to using ethernet out of the streamer port of an Innuos Zenith mkiii into the ethernet port of the Airlens, using the Innuos Sense app as UI ? Perhaps Innuos server users could help clarify if they are using another streamer currently that is a step up in SQ from running the Mkiii by itself? Alternatively ethernet feed from router to Airlens using a different upnp UI, or many from a Roon server feeding Airlens as an endpoint. Looking 3 months out to Airlens install and would like to hear the best options and ideas, thanks guys, and cheers.
I am most satisfied with the INNuos ZENith Mk III streaming capabilities when used with the INNuos Sense app sans Roon. As the Air Lens is yet to be released there’s no point in considering feeding the INNuos to the Air Lens. That said the upgrade I’d consider based on Al’s discussion is a Grimm MU1. As I am currently satisfied with my INNuos, the move isn’t a near term priority, and by the time I decide the market may have shifted.
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I feel that way about the DSD MkII!
@weedeewop true, yet the Grimm is 6x $ the Airlens, and perhaps my query is whether it’s worth adding an Innuos server with ethernet out to Airlens just to have the Sense app as UI?
Why not just go with the Innuos and be done with it, especially considering a firm release date for the Air Lens has not been announced. As this is PS Audio’s first go around with the Air Lens my assumption is post release there will be user comments that need to be addressed regarding app functionality. The Innuos Sense App over is fine in my opinion. I get that the Grimm is expensive. So is the Innuos as one works their way up the Innuos line. One thought would be to pick-up a most basic Innuos Zen Mini to tide you over and try it with the Air Lens when it becomes available. You may take a bit of a “haircut” when reselling the Zen, but it shouldn’t be too bad. Regardless I wish you luck on your search.
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