UPnP v digital input.

Dave

Ultimately it doesn't really matter how you connect your HDX server to your streamer. In one mode it sends data packets via the network using the UPnP protocol. In the other mode it sends it via an isolated digital out.

If you have access to the NDS white paper, have a look at the diagram on page 3. The two data streams converge in the same module, before being sent to the SHARC processor.

Adam

Some people prefer the sound with a direct connection. If you are happy then you can safely leave it like that!

There has been quite a lot of debate about this with the new Uniticore. But I wouldn't say that there is any particular outcome yet.

best

David

Dave, it should sound fine... UPnP HTTP media transfer over Ethernet ( and TCP)  and SPDIF transport framing streams are just two different methods of conveying the exact same media sample data when sending PCM/WAV, albeit diced and sliced differently due to the different transport protocols used in SPDIF and UPnP HTTP media transfer over Ethernet. The processing of the different transport protocols by the streamer can/almost certainly add its own character (sounding different, possibly leading to a personal preference one way or the other) due to the extremely low levels of differeing electro-magnetic signatures generated by the circuitry/firmware processing the differeing protocols.

Yes UPnP can send different media types, whereas SPDIF stereo PCM only, so if you were sending FLAC by UPnP media transfer there would need to be an extra conversion stage in the receiver/streamer which may 'modify' the perceived SQ.

Many thanks for the replies received.

I'm using a fairly budget optical cable for the connection, so, as we've previously had some discussion about the merits of upgrading ethernet cables, is there any possible advantage in my seeking out a more upmarket cable?

Or should this thought be consigned to the "cables don't matter" bin?  

Can of worms duly opened! 

Dave - cables do matter. The better the cable, the less 'distortion' it introduces. 

I would actually suggest that you try a different digital out - via a regural digital 75 ohm cable.

From Audirvana plus blog with regard to UPNP:

“Audirvana Plus 3.1 prepares the working process of the network player. Any PCM format audio file is sent to a non-compressed WAV format thus, avoiding the network reader from performing decompression calculations potentially harmful to the sound quality. Any DSD format audio file can be transmitted directly decompressed (or transcript [sic] to PCM if the network drive does not support the DSD)”

I am not affiliated in any way to Audirvana, just find it interesting.

Today, I swapped out the generic toslink cable for an Audioquest Cinnamon, which is what I already use to connect my NDS to the ethernet switch, and, I really can't discern any difference in SQ between the direct optical connection which I now have, and uPnP which I was previously using.

So that puts to bed the unresolved network issues which seemed to be causing the UPnP problem.

Life's too short for head scratching, bring on the music! 

Happy to hear that Dave!

Enjoy the music.

Adam

Come on, Dave, behave. No one from Northallerton or thereabouts 'swaps out'!

Best, Chris

Christopher_M posted:

Come on, Dave, behave. No one from Northallerton or thereabouts 'swaps out'!

Best, Chris

Ey up, what's tha mean? 

Hi Dave - did your HDX upgrade work out ok ?

james n posted:

Hi Dave - did your HDX upgrade work out ok ?

Yes James, perfect, and it would have been easy to blame the UPnP problems on the upgrade, since it was working before, but everything's fine now, using the direct connection via Toslink.

It now means controlling music replay on the iPad via nServe, rather than the Naim app, which is now used only for remote volume control, but hey ho, who cares, since it sounds exactly the same anyway.

There was much discussion some months back about the merits of upgrading to classier ethernet cables, and I have changed out the basic Toslink cable for an Audioquest Cinnamon, and either, the same principle applies, or I'm far too easily led. 

Anyway, it's something of a pointer for anyone experiencing network issues, as connecting the server and the streamer directly, as I have done, seems to take care of things.

Hi Dave,

Toslink can be a surprisingly good way to link digital devices. While other interfaces can offer higher bandwidth and/or lower jitter, the galvanic isolation inherent to Toslink may outweigh those in some cases. My NDAC sounds better fed by a MacBook via Toslink. S/PDIF, even using a good CD-Player as source and a good cable was clearly inferior. Both were non-Naim products, but still an unexpected result.

 I used the Cinnamon for the initial comparisons and settled on a (hopefully) better cable with glass fibers instead of plastic ones for my system. The Supernova from Wireworld and the AQ Diamond are well regarded examples of this design.

With NDX and NDS both digital inputs are gavanically isolated. Opto due to its nature, coax via a high-speed pulse transformer. 

Indeed, both the digital inputs and outputs are galvalically isolated on the NDX, according to my trusty Fluke meter. They key benefit of Toslink over Coax is that it 100% rejects common mode noise. The Galvanic isolation is a red herring... if one didn't have galvanic isolation one could really get into a pickle with earthing and grounding loops.

dave marshall posted:

Today, I swapped out the generic toslink cable for an Audioquest Cinnamon, which is what I already use to connect my NDS to the ethernet switch, and, I really can't discern any difference in SQ between the direct optical connection which I now have, and uPnP which I was previously using.

So that puts to bed the unresolved network issues which seemed to be causing the UPnP problem.

Life's too short for head scratching, bring on the music! 

 

Interesting! So there is no difference in SQ between UPNP and toslink? I have always thought UPNP is better, and that is why I have never bothered to try direct cable, be it USB, SPDIF, or Toslink.

banzai posted:

dave marshall posted:

Today, I swapped out the generic toslink cable for an Audioquest Cinnamon, which is what I already use to connect my NDS to the ethernet switch, and, I really can't discern any difference in SQ between the direct optical connection which I now have, and uPnP which I was previously using.

So that puts to bed the unresolved network issues which seemed to be causing the UPnP problem.

Life's too short for head scratching, bring on the music! 

 

Interesting! So there is no difference in SQ between UPNP and toslink? I have always thought UPNP is better, and that is why I have never bothered to try direct cable, be it USB, SPDIF, or Toslink.

My ageing ears can't discern any difference, and this seems to be borne out by the views of some of our resident networking experts here, and the mighty Phil Harris, who responded to me along similar lines by email.

Mind you, my aural receptors are not the best, and the theory is just that, theory.......... try it, and let your ears decide. 

Thanks Dave, that gives me some thoughts ... Maybe I will reconfigure my system and hear it for myself. My system is a highly regarded streamer and it is ethernet-wired to the same network as the NAS (and a Mac Mini).

dave marshall posted:

banzai posted:

dave marshall posted:

Today, I swapped out the generic toslink cable for an Audioquest Cinnamon, which is what I already use to connect my NDS to the ethernet switch, and, I really can't discern any difference in SQ between the direct optical connection which I now have, and uPnP which I was previously using.

So that puts to bed the unresolved network issues which seemed to be causing the UPnP problem.

Life's too short for head scratching, bring on the music! 

 

Interesting! So there is no difference in SQ between UPNP and toslink? I have always thought UPNP is better, and that is why I have never bothered to try direct cable, be it USB, SPDIF, or Toslink.

My ageing ears can't discern any difference, and this seems to be borne out by the views of some of our resident networking experts here, and the mighty Phil Harris, who responded to me along similar lines by email.

Mind you, my aural receptors are not the best, and the theory is just that, theory.......... try it, and let your ears decide. 

Funny, because I need to use toslink on my side for the usage of Roon in my 272, and it still sound very good to my ear, was very surprised. I did some back and forth between UPnP and Toslink (16/44), and no, really, the diff, if there's a perceptible one, didn't pop to my ear.