T+a dac 8 dsd

[Miska]

Rob on DSD:

 

The babble was too-long-didn't-read for first iteration for me. But it contains some annoying errors.

 

Well any signal that is below the noise floor of the noise shaper is completely lost - this is completely unlike PCM where an infinitely small signal is still encoded within the noise when using correct dithering. With DSD any signal below the noise shaper noise floor is lost for good.

 

This is complete bullshit.

 

The point I am making over this is that DSD noise shapers for DSD 64 is only capable of 120 dB performance

 

This is also bullshit. I can do better for DSD64, and as a result 24-bit PCM input is limited by the 24-bit PCM noise floor rather than the modulator.

 

For DSD256+ I can do better than 32-bit PCM.

 

 

Rest of the story is just funny, because DSD is just delta-sigma and Chord DACs are delta-sigma DACs.

 

DSD is only limited by the modulator implementation quality. Theoretical maximum dynamic range of DSD64 is 385 dB, for DSD128 it is 771 dB, for DSD256 it is 1541 dB and for DSD512 it is 3083 dB.

[juanitox]

I think it's really a personal taste. You should try DSD and see for yourself.

 

Personally, at this moment, I don't use HQPlayer, but Daphile, but I do upsample everything to DSD256 with an ifi nano DSD. If the music sounds sooooo bloody good (at least to my ears and with my mid-fi equipment), I can only imagine what the combo of HQPlayer and a better DSD DAC will do in the future!!!

Food for thought...

 

i am open to evolve , perhaps not with a expensive dac like the T+A at first , what was your PCM dac before the Ifi nano ?

[One and a half]

Well, if you are already up-sampling everything to DSD128 why not then to DSD512 if it will give you better sound quality. And until you try the T+A it my sound better then what you have even at DSD128.

Only by trying can you have your answer.

 

PS I think that the Tidal is only for a limited time period so does that mean a whole lot. Maybe it is for you.

 

USB needs fixers So far the solution I have works, and rather stay with that for the time being. The flexibility of the Simaudio 380 has the edge over the the T&A using the loop function. This is complex please bear with me. As stated I have three RCA coax sources plus an optical. I could use a manual selector method which is USD650. Added to this is an SRC device to increase the sampling rate, since I can't use HQPlayer for digital level sources and it's more complex, since when do I need a computer to listen to the radio??

 

If the 380D or the DAC 8 are used, I avoid the expense of the manual selector due to the number of inputs to those DACs that's a plus. With the DAC8, I would need a multichannel (8) pro device to SRC to input into the RCA coax. For the 380D only a 2 channel SRC maybe with a re-clocker device is required, and if the loop is not needed, it's switched out, simple.

 

I cannot afford the space to have both DACs, so a choice needs to be made for flexibility, so far that is favouring the 380D. I tried DSD256 with HQ Player for a few weeks, I'm not a golden ear, it didn't work for me, not really rapt with the sound. DSD128 worked out far better, is a sweet spot as far as keeping the PC working with a lot less overhead with enjoyable sound quality.

 

I don't use Tidal now, nor in the future, but it's available.

[One and a half]

Yes... Since that one is still compromised in the DSP chain, it would be nice to get cheaper variant of the same DAC with the "PCB1" removed and replaced with simple DSD-only input capable of DSD512/DSD1024/DSD2048.

 

Agreed.

[chrille]

You can find some DSD256 recordings from nativedsd.com

 

 

 

I don't make any compromises in HQPlayer. Objective of HQPlayer is to replace compromised DAC's DSP processing with better one.

 

 

 

Probably those, and bunch more. I have more DSP things in scope that for example DAVE doesn't do. Such as running digital room correction and X-over filters, also for DSD content and such.

 

 

 

Since HQPlayer doesn't make any compromises (unlike for example Chord Hugo which seems to have compromises in the DSP), you can run no-compromises upsampling even with $500 DAC, or $5000 DAC. I think that is much more interesting. Of course the analog sections and such don't get replaced by doing this and thus you may still have some compromises with the $500 DAC.

 

Think it from this point of view; what if you would leave out all digital processing from DAVE and leave only the actual conversion and analog sections. All digital filters, modulators and processing could be left to player software running on a computer. Then it could leave out FPGA altogether and be implemented with just the Atmel chip that deals with USB interface. That way it could be much cheaper DAC with at least the same or possibly better technical performance!

 

 

 

Nice to know money is not an issue for you, but many other people have limited budgets.

 

 

 

I have Mojo and it can be improved with external upsampling. If it would have a direct mode bypassing all DSP processing it would be even better.

 

Thanks for your response but 1: My 1st question was if YOU know any ADC that actually records DSD 256 NATIVELY, not where you can buy DSD256 albums.

You did not answer my question.

 

2:Your answer regarding "interpolation magic upsampling" seems more like you are guessing than really know what "your interpolation magic" actually does?

"Probably" doesn't sound very convincing to me.

And "a bunch more".What more?

 

3: I have never said that money is not an issue for me, only that my taste is for the very best possible SQ without compromises.

If that could be achieved without rip off pricing I would be a very happy music lover indeed.

But as you say cheaper DACs will still be compromised by the cheaper less transparent analogue parts used.

 

4: As far as I know Rob Watts has categorically adviced against any external upsampling with his DACs.

He claims the opposite of what you are saying here. He claims it will deteriorate transparency and ultimate SQ with his products to do so.

 

It would be interesting to know what music and audio system you used to come to the conclusion that external upsampling of Mojo was an improvement?

Cheers Chris

[Hiro]

Latest AKM ADC chips can now record at DSD256 but there's not many (if any) implementations at the moment.

 

Andreas Koch is also working on a new native DSD256 ADC...

 

[video=youtube;N-BMl-l6KDY]

[Hiro]

Thanks for your response but 1: My 1st question was if YOU know any ADC that actually records DSD 256 NATIVELY, not where you can buy DSD256 albums.

You did not answer my question.

 

Merging's Horus is apparently the only ADC that can record natively at 11.2896MHz at the moment, but with latest AKM ADC chips: VERITA AK5572EN, AK5574EN, AK5576EN, AK5578EN (all capable of native 256Fs DSD conversion) we should see more such devices on the market soon. Playback Designs has also a new DSD256-ready ADC on the way (see post above).

 

Personally, I'd expect to see more ADCs that can do native 11.2896MHz DSD recording in the future, than native 352.8kHz PCM. AFAIK all current PCM ADCs are delta sigma ADCs.

[EuroDriver]

Mmmm, putting it that way makes it easy for the naysayers to dismiss it as marketing propaganda for the upcoming device you are working on. I wish you were not right, I wish that the NAA solution was the better one but now that I am reading about the microRendu I realize you are so right.

 

That is because DSD is a very strange animal, in fact it is analog signal that is handled as a digital one. And where actually it becomes analog is not very easy to say. So you experience that the place where it all happens - upsampling right there on the computer site and the need for good PSUs and precision clocks is unfortunately very very right... And it was so nice to think that the NAA is the easy solution, it is indeed very important but when you are doing the upsampling on a computer sadly you will be very right that you need to squeeze every single bit. Sadly is not the right word as truth cannot be sad, more appropriate is expensive...

 

IMHO you have hit the nail on the head , + 1

 

It's why we spent so much time and effort on the OCXO to get 10,000 times better frequency stability, and the lowest possible low frequency phase noise at a sub astronomic cost.

 

It's also why we have had to spend endless hours to get the OS to be as process timing friendly as possible

[jabbr]

Yes... Since that one is still compromised in the DSP chain, it would be nice to get cheaper variant of the same DAC with the "PCB1" removed and replaced with simple DSD-only input capable of DSD512/DSD1024/DSD2048.

 

With DSD1024 and 16 channels we are limited to 1gbs Ethernet input (720mbs) assuming the NAA protocol is efficient, but we could go to 10Gbe if needed

[ted_b]

You are correct as far as 2L is concerned. Morten records everything in DXD. He could have recorded DSD128 long ago if he had wished to.

I asked why he did not when I saw the DSD128 option on his ADC at some sessions. His answer was DXD sounds better.

 

Regarding native DSD.com a lot of what they have is natively recorded,especially those from Channel Classics. But with other labels represented if varies quite a bit.

Those from Challenge Classics at DSD 64 from native DSD.com are probably in most cases from DXD masters.

At least that is how that label's own site offer them from DXD through all available DSD rates.

But Bernt van der Wolf of Challenge Classics says that via some DACs his DXD masters will sound better as DSD 128 or DSD 256.

The Reference Recordings DSD releases also seem to be native DXD masters in some cases.

 

It does in fact seem as most labels even those releasing DSD are in fact recording in DXD.

I wonder if there are any native DSD 256 1 bit recordings made at all?

Quite a few labels use Merging ADCs which can output DSD. But do they really record DSD 1 bit natively?

The only true native 1 bit ADC used today that I am aware of is the Grimm Channel Classics uses. But it is limited to DSD 64.

 

As many of you know, if a label/artist/producer wants to edit this analog thing called DSD they, almost invariably, need to send it to DXD first. If that editing is simply cutting it into tracks or editing out mistakes then the "DXD'ing" is only in those minimal time domains. If they want to eq, sweeten, etc then they produce a DXD project. Any any case these are then converted to, eventually, a DFF master to be sent to (previously) the SACD plant or now to our facilities. Those labels that record in DSD but eq in DXD often send us, at our prompting, the DXD files now, too, so those of you with great ladder DACs can have the best of that world too. Why not?

 

Net/net, we care that the recordings (or in some cases direct analog transfers) are done natively in some form of DSD. Jared (Channel) does his mixing in analog so his results are in fact DSD. And yes, with ADCs like the Horus we get true DSD256 recordings from labels like Eudora, Just Listen (our own Horus-based fun), some of our Budapest sessions files and now more (Yarlung for example) and more labels are sending us DSD256 recordings. it's quite a fun time in our little neck of the woods.

 

Note: I am not technical, so I may have simplified. Tom may cut in here.

[jabbr]

Probably those, and bunch more. I have more DSP things in scope that for example DAVE doesn't do. Such as running digital room correction and X-over filters, also for DSD content and such.

 

yes. It is widely acknowledged that CPUs are much more efficient at certain algorithms than FPGAs and conversely -- to the extent that FPGAs when standalone, typically need to implement a little CPU eg a "microblaze" controller. In the future we will see an increased use of the hybrid approach (particularly from Intel) but Xilinx's Zynq is becoming more popular and affordable.

 

In any case don't assume that an FPGA can compete with a CPU/GPU approach in a cost effective fashion.

 

Since HQPlayer doesn't make any compromises (unlike for example Chord Hugo which seems to have compromises in the DSP), you can run no-compromises upsampling even with $500 DAC, or $5000 DAC. I think that is much more interesting. Of course the analog sections and such don't get replaced by doing this and thus you may still have some compromises with the $500 DAC.

 

Think it from this point of view; what if you would leave out all digital processing from DAVE and leave only the actual conversion and analog sections. All digital filters, modulators and processing could be left to player software running on a computer. Then it could leave out FPGA altogether and be implemented with just the Atmel chip that deals with USB interface. That way it could be much cheaper DAC with at least the same or possibly better technical performance!

 

Why not replace the Atmel with Zynq and get the best of both worlds. ? Much better handling of multiple clock domains. Only slight increase in price which is waaaay more than offset in not having to deal with weird USB cables and little boxes and connectors that are metastasizing all over them these days. Those are getting rather expensive themselves.

 

and then you can devote effort at high end isolation and reclocking of the native DSD signal, coupled with a high end analog section. As you said, that's where $500 turns into $5000

[kravi4ka]

IMHO you have hit the nail on the head , + 1

 

It's why we spent so much time and effort on the OCXO to get 10,000 times better frequency stability, and the lowest possible low frequency phase noise at a sub astronomic cost.

 

It's also why we have had to spend endless hours to get the OS to be as process timing friendly as possible

 

Well, I intentionally did not hit it full strength on the head, I would have needed to present more evidence that I am not just being a smart ass on a forum

 

I said it because when you were describing what you were doing and then I read about the microRendu I realized that there is more to computers that I know and I went and spoke to a friend who knows a bit more, he was one of the people who designed the GSM standard and was actually designing the chips at Alcatel Belgium.

 

His version was that when you are upsampling to such frequencies you do need utmost precision and everything will affect the results. So you are probably very right saying that it sounds different and better,I haven't heard your device but my friend says it will definitely bring improvement as the last thing on the mind of a computer board engineer is what is important for audio, it just needs to work and it sounds that you are addressing some of the inherent problems there(I am not affiliated with EuroDriver or his company in any way other than a few PMs). And that is custom work and custom work is always expensive.

 

But he said that computer is an experienced Devil and the right thing to do is what the microRendu guys are doing-design from scratch , just need to wait for 2-3 years and the microRendu will do it properly as optimizing hardware and software is the way to go.

 

An OS does many things at the same time, he was explaining to me once that even though we see the immediate results of a pushing of a button it is ages in computer time and the OS does at least a hundred other things that have been given priority. Later I read that again said from one of the prominent engineers here and since then I trust him 110%.

 

His advice was to either wait for the microRendu to grow up or buy your version if I want to upsample to DSD512 now. Or pay him design a SiC

 

Ignorance is bliss, I plan to leave PCM guys and DSD guys do the best they can and in the mean time I am saving for a DAC 8 DSD which can do both

[guiltyboxswapper]

Will be conducting an experiment later - connecting the T+A to my dirtiest computer to hand, an i7 Quad Dell with Win10 system latency all over the place.

 

Firstly this system cannot cope with DSD 512 with poly-sinc-{anything} quite frankly, so proved to be a bit pointless. I did do a quick back and forth in DSD 256 mode, to which there was certainly nothing obvious between that of the MacPro 6 core and the Dell i7 (4712HQ). Both with the Intona in place. I suspect the Intona 'neutralises' matters given that it repackets and reclocks.

 

And no, I'm not going to list out all of my reference tracks....

[guiltyboxswapper]

It's worth mentioning that the Dell clearly is a noise monster in its own right. This particular Win10 install that I rarely use has DPC/ISR issues all over the place, but I don't care to fix them with ETW tracing as its my 'worst case' machine to hand.

 

It's no lie, as mentioned above most PCs are truly noisy devices. You can feel earth issues just touching the chassis in certain places with the PSU plugged in, so was expecting a little difference at least. Looks like the Intona is doing what it said it would.

 

As for OS, one one save a lot of time and hassle optimising a Linux based system than a Windows OS - half the work is already done for you by others, for a start :-)

[hifial]

Firstly this system cannot cope with DSD 512 with poly-sinc-{anything} quite frankly, so proved to be a bit pointless. I did do a quick back and forth in DSD 256 mode, to which there was certainly nothing obvious between that of the MacPro 6 core and the Dell i7 (4712HQ). Both with the Intona in place. I suspect the Intona 'neutralises' matters given that it repackets and reclocks.

 

And no, I'm not going to list out all of my reference tracks....

 

 

Could you try the same, DSD256, with the Intona removed and see if you hear any difference? Not saying you will just curious.

[Miska]

In any case don't assume that an FPGA can compete with a CPU/GPU approach in a cost effective fashion.

 

I'm actually quite happy about how latest Intel CPU combined with latest nVidia GPU performs. CPU is good at doing few very complex non-parallel things at high speed. And GPU is good at doing many simple things in parallel at high speed. This combined with several gigabytes of very high speed RAM provides tremendous possibilities for things like complex adaptive/look-ahead algorithms. Entire album can be pre-analyzed to know upfront what is coming up and when. Combining the two gives best of both worlds. And nVidia's new Pascal microarchitecture seems to give a huge boost for HQPlayer-style applications

 

Why not replace the Atmel with Zynq and get the best of both worlds. ? Much better handling of multiple clock domains.

 

Sure, I just said Atmel because Chord uses Atmel MCU for the USB interface implementation. It can deal with two clocks fine, but of course with more flexible choice there are more possibilities and flexibility (for things like DPLLs and such).

[guiltyboxswapper]

Could you try the same, DSD256, with the Intona removed and see if you hear any difference? Not saying you will just curious.

 

I'm quite sure I'll hear differences. As mentioned above the machine is a noise nightmare. I'm going to see if I can output to file the DSD output generated from HQPlayer, and then use that exact output replayed on both systems in DSD 512 mode.

 

Still want me to try?

[Miska]

2:Your answer regarding "interpolation magic upsampling" seems more like you are guessing than really know what "your interpolation magic" actually does?

"Probably" doesn't sound very convincing to me.

And "a bunch more".What more?

 

I know what my stuff does, but I don't have very clear picture of what exactly Chord DAC does. So I cannot say if the goals match 100% or if there are differences. You are never going to get clear answer if you ask me to compare my stuff against some else's, because I cannot get inside someone else's head.

 

I said that the "bunch more" is things like:

- Digital room correction (convolution engine)

- Digital cross-over filters for speakers

- Digital re-routing and mixing

- Multichannel speaker distance and level adjustments

- Sampling rate conversions for DSD, both up and down

 

All this for DSD sources of any sampling rate too, to either DSD or PCM output.

 

How does your DAVE play 2L's 5.1 channel DXD content? You know, 2L is all about multichannel audio. I'm playing it all fine upsampled to DSD256 through my exaSound e28 DAC.

 

3: I have never said that money is not an issue for me, only that my taste is for the very best possible SQ without compromises.

If that could be achieved without rip off pricing I would be a very happy music lover indeed.

But as you say cheaper DACs will still be compromised by the cheaper less transparent analogue parts used.

 

So my objective is to make cheaper DACs less compromised by providing uncompromised upsampling and delta-sigma modulators. And in addition allowing cheaper no-compromise DACs because DAC doesn't need to perform any digital processing, just convert digital input to analog at highest possible quality - which is actually the connection to T+A DAC8 DSD in this thread!

 

4: As far as I know Rob Watts has categorically adviced against any external upsampling with his DACs.

He claims the opposite of what you are saying here. He claims it will deteriorate transparency and ultimate SQ with his products to do so.

 

Of course he does, but it is precisely type of blanket statement I just ignore because he possibly cannot know if any external upsampling is better or worse than what he's budget-limited DSP implementation does.

 

But with such statement, I would just advice people to primarily look at other DACs where manufacturer doesn't make such blanket statements.

 

It would be interesting to know what music and audio system you used to come to the conclusion that external upsampling of Mojo was an improvement?

 

Music is all kinds of stuff I have in my library. Headphones are Sennheiser HD800. Plus of course bunch of measurement gear.

 

 

P.S. I don't really understand WTF this Chord Dave discussion has to do with a T+A DAC8 DSD thread? I would suggest to start a new thread about Dave and suggest Chris to move related discussion there. Of course it is in a sense interesting that DAC8 DSD seems to be able compete straight against much more expensive DAC. Maybe because Chord is compromised in a way that it is not able to do native unprocessed DSD512...

[YashN]

I have Mojo

 

Well said

[YashN]

am i the only one one earth using HQPlayer reading straight 16/44k PCM files with no oversampling or dithering and find it very good ( ok i have a R2R pcm dac ) . or am i really missing something with all the DSD stuff ?

 

Pure NOS PCM on a well-made NOS DAC can sound really good indeed.

 

Only way to find out if you're missing something is to give it a try!

 

Best way to try: on a native DSD DAC, or a chip-less DSD DAC.

[YashN]

Since that one is still compromised in the DSP chain, it would be nice to get cheaper variant of the same DAC with the "PCB1" removed and replaced with simple DSD-only input capable of DSD512/DSD1024/DSD2048.

 

Is it the kind of simpler non-compromised implementation that T+A refer to as their discrete true 1-bit circuit?

[Hiro]

am i the only one one earth using HQPlayer reading straight 16/44k PCM files with no oversampling or dithering and find it very good ( ok i have a R2R pcm dac ) . or am i really missing something with all the DSD stuff ?

 

Ladder PCM DACs often suffer from linearity problems, aliasing artifacts, and zero-crossing distortion.

 

In the DSD world there is no zero-crossing distortion, there are no aliasing artifacts, and linearity is very good indeed.

[bmoura]

I'm actually quite happy about how latest Intel CPU combined with latest nVidia GPU performs. CPU is good at doing few very complex non-parallel things at high speed. And GPU is good at doing many simple things in parallel at high speed. This combined with several gigabytes of very high speed RAM provides tremendous possibilities for things like complex adaptive/look-ahead algorithms. Entire album can be pre-analyzed to know upfront what is coming up and when. Combining the two gives best of both worlds. And nVidia's new Pascal microarchitecture seems to give a huge boost for HQPlayer-style applications

 

I don't see a lot of advertising of PCs and Laptops with CUDA architecture. But it looks like a tempting combination. And perhaps an alternative to strictly focusing on higher powered Intel CPUs for upsampling to Multichannel DSD 256 on your exaSound e28 or the NADAC.

 

Are there examples on the market of CUDA-equipped machines you would recommend with HQ Player - and DSD 512 playback on the T+A?

[YashN]

I don't see a lot of advertising of PCs and Laptops with CUDA architecture.

 

It's not really something they would advertise directly, since CUDA is a software library.

 

So, to look for CUDA capabilities, you actually look at the video cards (or integrated Graphics card if a laptop). NVIDIA will have de facto CUDA support.

 

[EDIT] I will add that a certain amount of direct marketing is done towards segments which do make a lot of use out of this, namely gamers and also AI researchers/users.

[Miska]

I don't see a lot of advertising of PCs and Laptops with CUDA architecture. But it looks like a tempting combination. And perhaps an alternative to strictly focusing on higher powered Intel CPUs for upsampling to Multichannel DSD 256 on your exaSound e28 or the NADAC.

 

Are there examples on the market of CUDA-equipped machines you would recommend with HQ Player - and DSD 512 playback on the T+A?

 

CUDA is so much geared towards technical computing, that it is not advertised much to consumers. Practically most of the currently available nVidia GPUs are CUDA capable. At the moment nVidia's Maxwell-generation GPU architecture is best choice - usually meaning GeForce GTX 9xx series in consumer products. Also the professional Quadro Mxxxx series falls into the same category at higher price.

 

For a normal PC desktop there are many options and since the graphics cards are normal PCIe 16x cards, can be fitted on most modern desktop PCs. For laptops, there are number of gaming oriented laptops with GeForce 9xx GPUs and number of business oriented laptops with Quadro Mxxx GPUs.

 

nVidia just launched their newest Pascal architecture that promises huge performance improvement for HQPlayer-type computing tasks. First products rolling out during the summer and more towards Q1'17. The consumer product like is likely to be called GeForce 1xxx (1000-series).

 

Tesla-series is their HPC (HighPerformance Computing) product line, and the just announced

is pretty amazing.