Sonic deifferences between NDX and ND5 XS & other things

Posted by: Simon-in-Suffolk on 06 November 2011

I thought I'd throw this one out to the forum... I was having a nice cup of cha with my dealer yesterday and amongst other things the conversation came around to the NDX / ND5 XS. Although he had at that time no ND5 on show as the ones he had had he has sold, he said that they at the dealership had heard differences, and that the ND5 XS had a somewhat lighter balance to the NDX, and intriquingly he felt that also extended to when using it as a digital source rather than its own DAC.

He advised me they are going to do more of a proper comparison shortly to try and minimize other variables - but am intriqued if others have had a chance to notice this yet?

We also conducted another experiment on uPNP servers into the NDX , comparing UnitiServe, VortexBox and Asset on a little WHS machine. Other than VortexBox running FLAC, the other two were running WAVs but sounded clearly different. and quite honestly the Asset server sounded rather off, being muddled and slightly filtered. It sounded like RFI issues. We had no copy of wire shark avaialble, but I said lets check the network duplex and speed from the server as I suspected it might be TCPIP stack load casuing interference on the NDX. So hardwired Full duplex and 100 MBps on the server, it was auto before and network settings did change - I am not sure from what but it changed.

We then listened to the UnitiServe and Asset in A/B - there were still differences, but they were now tiny and the Assett was quite acceptable.

So observation is that the TCPIP stack on the server has an affect on the NDX sound - even if as pure digital transport. (in my opinion it shouldn't affect the sonic output) : TCP windows sizes, duplexity and speed.
Best set the network settings manually to 100Mbps and full duplex.
Finally it would be interesting to hear whether this 'feature' is elimiated aor severaly reduced with the new streaming boards.

Simon

Posted on: 06 November 2011 by Aleg

Originally Posted by Dustysox:

Hi Simon.

Forgive my ignorance how does one-

Best set the network settings manually to 100Mbps and full duplex.

In the tab Advanced of the properties of your Network Controler.

Navigation via Long route:

Control Panel
Network and Internet
Network and Sharing Center
Hyperlink behind "Connections: " of your active Network
Properties
Configure
Tab "Advanced"
Property "Speed & Duplex"
Value "100 Mbps & Full Duplex"

Short Route:

Control Panel
Hardware and Sound
Device Manager (under Devices and Printers)
Expand: "Network Adapters"
Right Mouse click on your network adapter and select Properties
Tab "Advanced"
Property "Speed & Duplex"
Value "100 Mbps & Full Duplex"

aleg

Posted on: 06 November 2011 by james n

Interesting observations Simon. Perhaps the issues you've noted above relate to the reported differences between NAS drives on the Critic forum ?

Can you explain more about the TCPIP stack overload. Is this generating more network traffic when this occurs ? My knowledge of TCPIP ends at the layers level so I'd be interested in an overview of what you think is going on.

James

Posted on: 06 November 2011 by Dustysox

Hi Simon.

Forgive my ignorance how does one-

Best set the network settings manually to 100Mbps and full duplex.

Posted on: 06 November 2011 by Dustysox

Originally Posted by Aleg:

Originally Posted by Dustysox:

Hi Simon.

Forgive my ignorance how does one-

Best set the network settings manually to 100Mbps and full duplex.

In the tab Advanced of the properties of your Network Controler.

Navigation via Long route:

Control Panel
Network and Internet
Network and Sharing Center
Hyperlink behind "Connections: " of your active Network
Properties
Configure
Tab "Advanced"
Property "Speed & Duplex"
Value "100 Mbps & Full Duplex"

Short Route:

Control Panel
Hardware and Sound
Device Manager (under Devices and Printers)
Expand: "Network Adapters"
Right Mouse click on your network adapter and select Properties
Tab "Advanced"
Property "Speed & Duplex"
Value "100 Mbps & Full Duplex"

aleg

Hi Aleg,

Great stuff. Thank you.

Ignorance Pt 2!!

Would this mean in my case NAS?

Posted on: 06 November 2011 by Simon-in-Suffolk

James, possible if the NAS also contains the uPNP server. The media (wav file) is sent as TCP. TCP uses a system of segments and windows and both devices will try and agree the biggest window of segments before an acknowledgement is made. If the sender (or receiver) has only a small buffer for the TXP then it is busy sending acknowledges. This puts increased network load on the TCPIP stack. If loading this stack causes RFI side effects like we have heard for FLAC processing, then it stands to reason that increased network processing will also cause side effects, this could be what I heard. Simon

Posted on: 06 November 2011 by james n

Ah ok - understood. Thanks Simon.

James

Posted on: 06 November 2011 by Hook

Originally Posted by Simon-in-Suffolk:

HI Simon -

So, obviously, there is nothing that can done on the NDX side of things -- it is what it is. That leaves the NAS side, or, the NAS + UPnP server side (if they are two separate boxes).

Are you saying that loading the TCP/IP stack on either the NAS or the separate UPnP server can cause RFI effects? If yes, are those effects airborne, transmitted down the ethernet wire, or both?

In my case, my NAS and UPnP servers are far away, in a closet in a separate room from my listening room. Everything is hard wired, but I have applied a few RF chokes to the back of the NDX. So not sure if there are any other precautions I can take.

Is there a way, for example, to allocate additional memory for TCP/IP device driver processing on my UPnP server (Windows 7), or is the buffer you are referring to already way down on a network interface chip somewhere? Or is the best idea to simply move the audio components on to their own, dedicated network?

By the way, and sorry for this brief aside, but I had my first ever irregularities with the NDX last night. First, there was some bursts of noise, pardon the crude analogy, but it sounded like brief farts coming out of my speakers while streaming some 16/44.1 content (and no, it was not an editorial comment on my music! ;-)). Then, when I switched to a 24/96 download, there were actual skips in the music (N-Stream kept incrementing, but the sound would cut out). I power cycled the NDX, and all was well again. I wondered at the time if the issue wasn't network related (NDX side processing), but I figured there was little sense in reporting this to Naim since I will be upgrading my network board in the near future.

Thanks!

Hook

Posted on: 06 November 2011 by Simon-in-Suffolk

Hi Hook, yes the RFI or high frequency noise I am thinking off is possibly generated in the piowerlines supplying the TCPIP board or chipset in the NDX rather than from any remote device. Also it may be in the later streaming boards, if that where the TCPIP stack is managed the situation is improved. We will have to wait and see. I can say that my home WHS running asset sounds great when feeding my NDX. Simon