Ok, I read this also a little late I have already ordered an Audio-GD Digital Interface but I think this is no problem. So, there is no hurry and for testing the NOS1 SPDIF, there will be somthing serious to which I can compare. 1200€ is of course not little money. And for that, the SPDIF driver should also be state of the art. I like experiments and testing, but developing while sending the gear 10x around would be difficult. You could design a spdif input for your NOS1. Maybe someone like to connect a bluerayplayer.., ah forgot, you would need a filter here. Anyway just an idea. So you could feed the nos own input. Maybe that would work without filter, just using 192/24 and arcpred.
Hmm... Investing 1200€ with the option of an upgrade to the real thing is attractive and makes sense. Without that option it would be not that interesting.
The PLL of my dac is quite good. It has 21ps jitter typically. Maybe there is a possibility to use the i2s signal (it will be possible somehow)
Is the spdif converterd to i2s before or after it passes the digital filter? It would be a nice option to use the analog part of the ref7 while using the digital part of the NOS1.

http://www.audio-gd.com/Pro/dac/RE7/RE7USB4.jpg

Great!
Oppo against lynx would also or even more interesting. Thanks a lot!

I can understand. Sure is sure (sicher ist sicher)

Yes, I must smile reading this. You could create a digital "Vinyl Filter" to make xx sound like vinyl again, just for fun.

I think so!

A few years ago I was buying a lot of vinyls, and every time I bought a new LP, I recorded it with my PC as 44.1/16bit wav. As I stopped listening to vinyl, I burned the files to DVD's as wav. I picked out one of them last week to look if the DVD's are still working. I didn't listen to them since years and I expected a bad quality from them. But I got surprised. The sound is realy good. No digital sound at all. Full bass and an involving easy sound. I would say it sounds very much as I remember listening to the original vinyl. There are three conclusions I would draw from here.
1.: If you record a vinyl it should still sound like a vinyl if you play them with your pc->So this would be a valid test for your system
2.: Something is wrong with the digital source material we get. There are some very good cd's but also a lot of CD's sound digital. Somewhere, someone does not care and messes up the sound of the production.
3.: Do not trouble to much by recording vinyl with 24bit/192kHz. Why do you want to record the 96kHz noise or use ~144db dynamic range for ~60db dynamic range that you already have covered with 16bit (~95db)?

Try ThreadPrio = realtime and PlayerPrio = low. It should work without problems. tell me if it not. And if it works... how does the oppo compare to xx?

You are right (and I think it was you that suggested that from the beginning), I was using first 21,150; then 01,150; then 10,150 and now 00,100. Best option at the moment.

Sorry, was a mistake. I misinterpreted the table on the first page. Nevertheless, the behavior of the PCM1704 could be the same as the PCM1794A.

Measuring conditions were the same for all three sample rates according to the PCM1794A datasheet. THD+N is proportional to the sample rate, (table of page 3). 
In the case of PCM1794A, there is always 8x oversampling used. What bb has measured is for systemclock>352. But THD+N could go down for even lower systemclock!? I don't know how to measure THD+N but shouldn't it be possible to meassure it for a certain frequency range (20-20k Hz), while sample rates are different (like they did in the bb sheet)? Thinking about it, it seems strange if there were the absolute same THD+N for different systemclocks.

I think in the case of NOS1, it should be good with high fs, because the "upsampling" is part of the filter. It could get worse if the filter is designed for 44.1, and you just double to 88.2 without consider that in the filter. But I don't know how the doubling is done. I am speculating very muche here.

...time to sleep...

I think the useage of the tracks depends on how you are testing and judging what you hear. My methode to judge is to listen to records with most handmade music. I listen to the instruments on the record and try to compare them to the sound I know (from memory) from the real instrument. If there is something strange in the sound, if it sounds distorted there is something wrong. I chose the setting which brings me the closest to the natural sound of the instruments. That is the purpose to use high quality records. If I tune my system to a recording of a acoustic guitar that contains distortions (not heavy metal records ), I will tune in the wrong direction because I will try to mask the distortion of the record.
It would be the most easy, if we first share the music. I think the best tracks will sort out by itself. Everybody judges his system in a different way. So if "you" do it in a different way, just say to what "we" should listen to. We will see which tracks will be used. Important is, that we all have them to compare.

I have found something interesting for all people not using the NOS1 or an upsampling DAC. The picture below shows a graph that shows distortion of the PCM1794A for different sample rates over room temperature. The interesting thing is, that with higher sampling rate, the distortion increases! This is not what most would expect. I looked in the specs of the PCM1704 and it also produces higher distortion with higher sampling frequency. This may explain my prefered setting of 44Khz. There are for sure advantages of higher sampling rates but I gues if you like to benefit from it, the DAC must be designed to this frequency [Example: A possibility would be to use a "softer" filter with higher sample frequency. So less phase shift is produced]. And one can imagine, if your dac will produce higher distortion with higher sample rate, your cable and your usb device/soundcard might do this too! Higher frequencies means higer energies and more stress to the components. So if you got a normal OS dac, a soundcard or something else that is not the NOS1 or an upsampling dac, it can be better to use the native sampling frequency, because that is what your dac will be tuned to (worst case cenario). [And also ArcPred should not be used, it creates additional distortion if you have no NOS (Peter please corect me if I am wrong but I think you wrote this somewhere else).]

Thanks for the hint.
I tested HQPlayer with different upsampling methods and without upsampling. I think it is far away from xx, no matter if I use Engine3 or Engine4. HQ sounds very bright and unpleasant while xx gives more resolution and a deeper and finer sound with more bass and body. No option in my case.

I think the point is, it is not that simple. You need at first hardware that doesn't mess up the sound. Then you need an interface, software to control the unit and all that in an audiophile quality. No easy task, if you ask me. Linn majik might be close to what you are looking for but the price...and you get no good quality hardware. What you (we) want, can be done but it wont be cheap. You need people that know it all, from the software to hardware and with listening experience (if you want top quality).

Yep that is a flaw but I can live with that. The legato I was seriously thinking about is limited to 16/44. So I have found a fair compromise, especially when you look at the price (Thanks marcin for the hint!). Until my unit will arrive it will take some time (4 weeks) but I will report. I am looking foreward to your review!
Greetings Adrian

A pc that is optimised for audio, can not be a pc anymore. It has to be a unit that like chrisnee said, is stripped of everything. Everything that induces rf noise to the circuits. And striped of software, that makes the performance inferrior like windows or every OS that is meant to do a lot of different stuff. It needs speciallized circiuts to do the audio processing at best. Non the less, the pc is still a very inexpensive approach to get good quality sound. Windows x said he could not outperform his CDP and I realy beleave him. Maybe his system can be made better but I know from listening sessions with CDT's that it is not easy to beat even a moderate priced CDT. For example my old usb interface(hoerwege usb-spdif) sounds better than a 12 year old Pioneer PDS06. And that is possible since the newest and best xx configuration. A better CDP, the modified (10 years old) Pioneer PDS707 can keep it up with my hiface and maybe sounds better in some aspects. It is a good drive but there are a lot drives that are much better. I would not bet money, if there was a head to head comparison between best CDP+DAC and best PC+DAC. The classical CDP has the big advantage, not beeing a computer. And I think it should be possible for a good CDP to read the CD accurate, when my CD-ROM can do that with 7Xspeed. Goining back to CDP is no real option because there are so much more possibilities (hires, downloads,...) you have with the "pure" digital playback. Peters NOS1 might be the first approach that has the techniques to outperform any CDP. A comparison would be really illuminating.

I stumbled over it too. I am interested how it compares to your hiface. I ordered an Audio-gd Digital Interface. They both should outperform the hiface clearly.

I take that option to explain how it was. I read about the Vista "downgrade" with improved sound quality and of course wanted to try that. I expected a big change but my experience told me:" be carefull don't just jump on a train, be carefull!" So what I did, you all know. The big change was not there. I was sure, that there will be some difference and with Peters help, I could hear and name it. But it was not the night and day difference that I read about. "Difference to small to care about". Then I tried W7 SP1. Again, no big differece, if any at all. But it can be, that some important updates were allready on my PC because of auto update. And that again explains, why I didn't thought Vista is a lot better...maybe, maybe not. The most important thing is, that we are now all on the same Train with W7SP1. From here it will go foreward.
Happy new Year!