The problem now is, that I would not mind to pay a bit to open their measurements behind the paywall, but then we still could not discuss them here, because of their copyright.
Personally, I donāt think you should bother. If you look at the test setup diagram, thereās no DAC in there, theyāre measuring the Metrum Amber Streamer, not the DAC. 
ps: Meaning itās more than likely those results are very specific to just that use-case/devices, and it may not apply universally.
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You are probably right. I now rest my case, and will go to enjoy my improved bias 
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Not necessarily. Discussion is not the same as making a copy which is the relevant protected act. Just donāt post a copy of the piece. It may or may not constitute Fair Dealing anyway but that is a lawyerās point and Iām not a lawyer.
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Good point, Pete, but that would imply that many readers would have to individually open up these measurements. Good for the business model of Alpha Audio, indeed.
Edit: Another complicating factor is that the whole article, and the measurements and their interpretation, are in Dutch, so everyone wanting to open them would need to translate them by themselves.
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Alpha audio site has the option to choose english.
Donāt let Anupc bully you into thinking there are no differences in SQ to be had with Switches and their power supplies, I am convineced the difference you heared is there, I agree it is not the data, but the powersupplies to the switch can influence the SQ, I have tried numerous power supplies on my Melco S100, and they all sound different, I have settled now with an Ifi Elite SMPS which brings the best resolution in my system (and itās not a sublte difference, easy to detect).
Probably the ābiasedā comment will pop up again, starts being a bit condenscending IMO.
No one is bullying anyone.
Everyone here is free to come to their own conclusions.
I am happy to read the point of view of someone who works in the industry and is qualified to explain and answer these questions.
Much preferred to some of the āWhite papersā coming from an industry (Audio) known for its share of snake oil companies
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No problem, I donāt fully agree, but maybe my response was too much
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Managed switches (and more to the point - people buying them because āmore expensive must mean better, right?ā) have been an absolute nightmare for me for the last 20 yearsā¦
ā¦as have poorly performing Ethernet extenders (Ethernet over Powerline, WiFi to Ethernet Bridges, Ethernet over Coax etc.) that end up being used because āitās impossible for me to run an Ethernet cableā ā¦ the number of times that Iāve had someone check for problems by just temporarily running an ethernet cable and the kit has then suddenly started working fine but yet itās still seemingly presumed to be down to the streamer manufacturer to āmake it workā with the networking kit that isnāt working correctly rather than making the networking kit that isnāt working correctly work correctly.
People always presume that networking is difficult but it really isnāt ā¦ issues are almost invariably caused by people taking shortcuts. I often get asked āWhat features and functionality do you need for your kit to work so I know what to ask forā but we donāt need anything specific or unusual outside of the defined and accepted Ethernet specs - the networking kit just needs to work correctly which can be more of an issue.
ISP supplied routers have always been a bit of a grey area - I did some testing quite a few years ago on several different versions of āHomeHubsā that are supplied by a few related ISPs here in the UK and they would be fine and work perfectly UNTIL the point where network traffic reached a tipping point and then theyād start dropping UDP traffic on the WiFi network and would continue to do that until they were rebooted ā¦ unfortunately itās impossible for āusā to do anything to fix things like that.
Unfortunately the reply we often get is āBut my computer and phone are working fine so it must be your problemā and that isnāt necessarily the case - for example, if the computer and phone are using TCP when itās UDP thatās being messed up by a piece of network hardware then the PC and phone will work fine but - say - autodiscovery in a streaming device app will fail because the UDP / UPnP discovery will fail.
One thing that is definitely worth noting is that people often donāt help themselves by using Ethernet cables that are shielded and have shielded Ethernet connectors that directly connect the chassis ground of your audio streamer to the chassis ground of what might be a quite electrically noisy networking device. There really is no need to be using a firehose thick CAT27j Ethernet cable (no, there isnāt a Cat27j) that can handle 200Gbits/sec of bandwidth when even UNCOMPRESSED 24bit/192kHz stereo audio can be handled (OK, only just with overheads) by 10mbit Ethernet which was superseded 30 years ago. 100meg Ethernet is an order of bandwidth more than is needed for 24/192 and Gig Ethernet is another order of bandwidth more than needed again.
Also, be aware that heavy and stiff Ethernet cables (especially when they are also using lovely looking big metal Ethernet plugs) can put a huge amount of strain on PCB mounted Ethernet jacks and over the years I have seen Ethernet ports leveraged away from boards because of the strain applied by such cables and connectors - a simple decent, certified, Cat5e or Cat6a unshielded Ethernet cable will prevent chassis noise being transferred from a downstream device into your streamer.
I also get that fibre is being used to electrically isolate audio devices from the rest of a network using inline Ethernet to fibre transceivers but remember that those CAN also generate their own electrical noise themselves so just be aware of that and the above notes on Ethernet cables still apply for those being run between an audio device and an Ethernet media transceiver if you go down that routeā¦
BR
Phil
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Thanks Phil. Great info. B
Excellent info Phil; thanks much. Simpler does indeed seem better.
Thank you very much Phil.
Is it accurate that dCS streaming (and maybe most streaming?) uses UDP data transfer protocol, and not TCP?
Steve, on the dCS platforms itās all TCP based.
Both UPnP as well as RAAT (Roon) are TCP based locally, and with the Streaming services - Tidal, Qobuz, Deezer, Spotify - are all TCP based streams directly into the dCS DACs.
IIRC, Roon used to be UDP based, but they switched with RAAT (Roon Advanced Audio Transport) to be TCP based.
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I think this one explains it all:
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Thanks Erno! I hadnāt seen that particular post from Brian before!
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Brian is a genius!
Everyone interested in Roon, how it is working, and why so, should save this document for future reading, or even print it and hang above your bed 
Roon RAAT.pdf (135.6 KB)
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Indeed, both Brian and Danny are among the best in the industry IMHO; theyāre been doing network based Audio streaming for a very long time (I was on the verge of acquiring a Sooloos system just before Meridian acquired them).
Speaking of which, not to open another can of worms, but Iām curious on your personal take, subjective or otherwise, on the whole dCS DAC Mosaic/UPnP vs. Roon/RAAT sound quality debate? Care to weigh in publicly (or not, your choice, no pressure ).
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Maybe this belongs to a separate topic, but I never use Mosaic for music playback because I prefer the convenience of Roon. For the rest, I am with this:
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Ahhh, makes sense, especially given your souped-up Roon core 
Not sure it warrants a separate thread though; there will always be a fringe few who donāt quite get something right in their set-up (or are over-imaginative ) and hear a difference despite such a clear statement of fact from dCS;
We both referred to the same post 
Over the years home audio has shifted from analogue to digital. From vinyl, cassette and tape to streaming, and DAC. From physical media connection to abstract. From media you can hold, see, and manipulate to just consume. All progress in SQ comes at a cost. To get it right asks for more knowledge.
To be honest, back in the days, I enjoyed listening to analogue music actually even more than I do now. Despite the improved SQ.
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