Dedicated Modem

[Moving from another thread]

Question for the tech experts in this forum.

I currently own a dCS Vivaldi and I would like to improve the sound quality of any streaming source.

I am wondering whether anyone has ever tried connecting a separate, dedicated modem directly to the upsampler/streamer. By separate, I mean a dedicated modem with its own fiber connection (and yes a separate account and I guess IP address).

I have now purchased a long ethernet cable from Entreq (grounded cable) which I will use in order to connect my Vivaldi upsampler to the Vodafone modem (via the ethernet switch) (as my system is currently connected to the ethernet socket on the wall). [TBD whether in this new setup I will still need to employ the optic-fiber converter.]

As I said above, I am wondering whether a dedicated modem (used only for the audio system and separate from the “general” modem) could add value in terms of SQ. I am sure that the modem which feeds everything in the house injects every sort of noise into the audio system. Does this make sense? Han anyone tried it?


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No, I don’t see that helping @Frankie67, or at the very least if it does, and it really shouldn’t theoretically, there are cheaper and easier ways to achieve the same thing. My suggestion would be to try one or two back-to-back externally clocked switches (like EtherREGENs but there are lots of options here) connected with ethernet cables with the shield lifted at one end.

I know Anup says this is all poppycock and we are all just imagining things, and I respect his opinions and have no wish to wake the sleeping bear, but in Paul Miller’s lab report which accompanied Andrew Everard’s review of the Melco S100 switch published in Hifi News he found repeatable reductions in jitter from inserting the switch between ~1 psec (worst case) and 5 psec (best case) and an uncorrelated noise reduction of 0.4dB measured at the analog output.

Remember these improvements were derived from inserting a switch into a packet network which is theoretically just a guaranteed delivery mechanism that the whole of the internet is built on and has nothing whatever to do with the time domain of digital to analog conversion.

However these are infinitesimal improvements, it is between you and your pocketbook to decide if they are worth the price of entry.

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Thanks. Wondering whether anyone has tried my idea. To me (but I am not an expert), it looks in theory like the optimal solution as it allows a completely dedicated line for audio data. That would be in parallel with a dedicated AC line, which I already have for my system. Looking for real life experiences. Anyone?

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I understand your thinking Franco but I just don’t think you will achieve any worthwhile improvement.

As I said, to the degree the packet clocking affects DAC at all it is really only the last switch before the DAC that should be capable of making any difference. However I think Paul Miller’s measurements show that something is going on here that we can’t fully explain but clearly is having some small measurable effect. There may of course be other things going on that we don’t even think or know how to measure or are below the tolerance of our measuring equipment.

I too will be interested to hear others’ views on this. I am an engineer by training and hate it when things don’t behave according to the accepted models.


I am just a lawyer (not an engineer by any means) but I’m also an audiophile and I strive for the best sound quality that I can achieve. Would love to hear if anyone has ever tried a separate internet server/ISP setup in real life.

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I did try this briefly as we had five VDSL lines running into my study (long story) and, no, it didn’t make a difference.

I found fibre in the house did help, but is SFP dependent.


Love it Jeremy! Nothing exceeds like excess!