Sound quality depends on where you save your files!

Guy - I think its more do with with Morphic Green Cream..

priceless - where did you find that....

Simon

Intriguing read Guy, I would like to comment further but am busy trying out the Free Sound Improving Techniques section, I have one corner of the curtain pinned back and a piece of paper under one foot of the power amp; amazing! Must get on, lots more to try.

Thanks again for more 1^st class information.

Peter

Dear Guido,

We can certainly dispute each other's claims and question each other's findings in this forum. However, we could handle each other's posts with more positive communication, now you are coming up with another post just ridiculing my original post, without serious examination or analysis thereof. You are a forum member, whose posts I usually find very interesting and I don't want to lose my respect for you.

The date of my previous post suggesting sq differences btw computer sources was 09 April 2011. During the eight months since then, I’ve been working on the o post of this thread, with numerous strenuous listening tests in different “humidity and temperature”, and “moods and states” (as you suggest), and even “spent few weeks in the country” in between, without the “white coats having to ask me” as Tog suggests. I am not a person who just posts after a few moments of listening one evening, although I also know to appreciate when members post such “first impressions”.

My anecdotal report does not claim to draw conclusions about the causes of the perceived sonic differences. Research with a “clear methodology for testing” (as Tog suggests) together with technical experts would be needed to clarify the complex technical issues involved and all these could contribute to better streamer designs. The same is true for the report in the HiFiCritic magazine. In fact, the discussion in the Hifi Critic Forum (by the most hypercritical persons) seem to point at possible artifacts created in the stream client (NDX) caused during varying interactions with the store location.

Interestingly, you offer one explanation in your post about why different NAS could sound different: “A badly made NAS installed at home that blasts RFI and EMI around the place will have an audible effect…” If this would be true, I would not refrain from calling that NAS as “inferior sounding”. It all depends on interactions in audio systems. I know, when I said " Each NAS out there must have a different sonic signature", I must add "in a given system". It would be too early to claim that this signature would be constant in any system. The Hifi Critic forum suggests, “conducted RF”, as well as “different processor activity patterns within the streamer (inducing jitter within the SPDIF transmitter) depending on the NAS drives, as different packet sizes, latencies, etc, all impact the data processing side of the streamer”. I personally tend to believe that the electronics in the vicinity may also be influencing store location hard-drives, which may alter data management patterns in the interaction with the streamer.

In fact, I see it as a defect of my post that I mentioned only this last possibility, although I did not intend to give technical explanations. Another shortcoming of my post is the absence of a NAS for further comparison (simply because I don’t have one). I searched in the forum for sonic comparison of internal drives of Naim server devices and computers with separate NAS drives. The only comments I could find were Harry on this thread preferring the playback from the NAS to HDX’ internal drive, and “chaps from the German Naim importer” preferring the HDX internal drive. So, a lot seem to be system (and taste) dependent.

In any case, digital music is apparently not only about “ones and zeros in a bitstream”. I agree with the editorial comment in the Absolute Sound: “Music may exist as ones and zeros in a file, but how those files are stored, extracted, processed, transmitted and decoded produce a staggeringly wide spectrum of analog-like variability in sound quality.”

Dear aysil

I most definitely did not mean to ridicule you; my sincere apologies if that was what you perceived me to be doing. Perhaps, my way of putting things across leads other forum members to think that of me. Shame really as it is not my intention.   

I shall try to refrain from posting in this section of the forum. I don't want to upset forum members.

My comments were directed at Hi Fi Critic not any forum members. I have lots of experience in the computer/network industry so my views are not without foundation. Sorry, but in my honest opinion, Hi Fi Critic is not a journal to which one should attach any credibility. The PWB Newsletter has more validity in my view.    

All the best, Guy 

Dear Guido,

I am not a follower of any of the journals you mention, so I should not comment.

Your criticism to my posts are certainly welcome!

All the best.

I would just say if I may, that it would be a huge pity if you did; and totally unnecessary IMHO. These are opinions that each is free to agree or disagree with after all. I appreciate reading both sides of the argument, each being valid points of view, again IMHO of course.

Peter

I second Peter's comments.

Guy, could you elaborate on why you think HFC is not credible? I can understand having issues with certain reviewers, but to discard the whole magazine? Are none of the reviewers credible?

I subscribed to see for myself whether freedom from advertising does in fact equate to freedom of opinion, or at least more credible opinions. From the three issues I've read, I'm not sure.  

Anyway, interested in your thoughts if you're open to sharing them here.

Jan

Gentle ridicule, humour, fun poking and flippancy ....... often quite powerful problem solving tools ... and they make the world a more enjoyable place.....

God help us if we start to take any of this or ourselves seriously 

Tog

Spoken as a true agnostic.

That's why they should be taken very seriously...

Guido said "Folks - data is being loaded in to a buffer and a DAC is reading it from the buffer, it doesn't know how the data got there, it doesn't care. That is whole idea of the buffer." 

That's exactly the same argument levelled at everyone who ever complained that certain kit was better at one type of music than another. Yet, in my view an LP12 can't do classical, a Michell isn't so hot at rock and a Xerxes wouldn't play jazz properly if the room was smoke-filled with the heavy odour of cannabis (well, maybe then...). Others will disagree with this, but where we agree is that they do sound different.

Now, if somebody is willing to accept that 3 record decks spinning at the same speed can sound different, why should it be any different for the vastly more complex subject of a TCP/IP network served by different devices?? A record deck has a motor, simple controller, bearing and a rubber band. That's it. Each electronic device has millions of active electronic components, a vastly complex controller, management subsystems. Conceptually, it comes down to a controller picking up bits off a disc and stuffing them into a buffer, packaging the data into a packet and delivering it to the network to be unpacked by yet another immensely complex bit of electronics and eventually decoded into an analogue waveform which is something they weren't even designed for in the first place. So why on earth would you expect all those different bits to come out with a side effect that sounds the same? The question is why don't they sound more different? And after all, if they were all the same, why are there so many of them, and why even when doing their primary function of serving files, do some seem to perform better than others?

Everything counts when building a system, so everything can have an effect. I too have worked in IT for 30 years and I too cannot understand how or why different computer peripherals should sound different. Perhaps I'm stupid, but I'm not going to discount the proposition merely because I can't understand or account for it. There are too many things I don't understand in this world already for me to have a problem with understanding why different components perform differently. I simply accept that they might, and try to develop a holistic system building approach to the subject.

Regards,
Frank.
All opinions are my own and do not reflect the opinion of any organisations I work for, except where this is stated explicitly.

Because we are in the computer world and data is data. Your sales figures on your Excel spreadsheet are not looking better from your NAS brand A than B.

IP packets do not know if they contain music, pictures, a novel or bank data... And they all arrive right or are rejected if wrong.

Streamers\players are not sounding the same, but they get the same data... at their input.

Data is data, and IP packets do not know or care what they contain. Music data is the only data which is converted into analog. No other data is converted into analogue, neither bank data, nor excel data, nor pictures. They are converted into different kinds of representational systems for communication. Music (sound) data seems to me unique in this respect. Even video is a sequence of still picture frames. Possibly, that's why factors which are not relevant for other kinds of data become relevant for sound, like PSU "strain" during "unpacking" in the streamer input depending on packet size, or like RF conducted on ethernet cable, which Simon fights with ferrite clamps, etc.

Another point of frequent misunderstanding, I think, is the claim that buffering (by nDAC) erases all jitter. First of all if the incoming clock information has already been degraded to have modulated the waveform, there is not much DAC can do. Secondly, although nDAC has an ingenious architecture to reduce S/PDIF induced jitter in a very exemplary way, it can not totally eliminate problems arising from differences between incoming clock information and its own master clock because "The rate at which the memory fills and empties is controlled by selecting the master clock that best matches the average incoming clock frequency." (nDAC White Paper) An average is never the exact value, because of the fluctuations of the incoming clock. "To cope with this eventuality we have also implemented, as a backup, an asynchronous sample rate converter (ASRC)" (ibid.) It is explained clearly in the paper that the use of ASRC is also not unproblematic. The paper is a wonderful source on the complex problems of DAC design...

Aysil,

I agree with you, all variations in sound quality come from the player\renderer and DAC, but not from the network.

There is no jitter consideration in an IP network.

IP Packets a unit gets are the same whatever NAS they come from.

For a network, music is EXACTLY the same as data, as pictures...

Yes, but influencing factors may be originating from the network, as discussed above and elsewhere on the forum...

As mentioned earlier I'm sure I heard a difference in a demo a little while back when listening to the NDX from different sources. I can't explain why and may be there were other external factors at play as suggested by Guy. However, I'm fairly certain based on tests that I have done that the PCM data that is stored on the NAS is the same PCM data that is delivered to the NDX in a streaming solution - I have verified this by recreating the TCP stream in Wireshark.

Of course, how it gets there is a different matter....so the two systems could be using different TCP window sizes or the underlying network might be configured to operate at different speeds - regardless the exact same copy of the data on the NAS is delivered by the network to the streamer. If there are errors on the network then redundancy checks should take care of this and the data will be re-transmitted.

So the the player/renderer involved may behave differently depending on how the data has been packaged up and sent across the network - could this be the source of SQ difference, I don't know?

I'll defer to Simon or someone who knows more about RFI but how would high levels of RFI impact on the network traffic? Would this for instance cause a one to be changed to a zero, if so wouldn't the built-in network redundancy checks take care of this. My guess is that high levels of re-transmission would cause drop outs in the audio rather than a deterioration in the SQ.

Trying to keep an open mind