World's first NOS 24/384 filterless DAC

[bhobba]

Peter,
It is still not clear to me how I should connect the NOS dac to my computer.
Do I need to prepare my computer in some way (hardware, connections?).
I understand that I have still some time to do that 
Cheers, Eric. 

I want to know that as well.  I asked a few questions trying to get to the bottom of it but never really got a reply - which is quite understandable of course since it probably touches on proprietary information.  But as a potential customer I think we at least should know what we need to do at our end.  With the availability of powerful notebooks that incorporate I5's I have decided against a dedicated PC in favor of a notebook with a long USB cable connecting where I sit (or lie in my case because of my bad arthritis - but that is another story) to the USB dac.  From a convenience point of view this is a real plus and I would need one hell of a good reason to move away from it.

Thanks
Bill

[PeterSt]

Peter

As you invited comments, let me expand on the issue of playing analog (vinyl LPs) and RIAA conversion through XX software and NOS1 DAC.

First, my thoughts to tranfer my vinyl collection (vinyl rip to 96/24 and save files to disc) was more driven by the convenience factor; with vinyl in digital domain benefits would be
a. stored in central digital music library and easily accesible (togteher with CD rips and digital dowloads) via computer network to play at any location in my home
b. ability to play vinyl tracks in any order (from one or several LPs)
c. possibility to play through XX and take advantage of its superior abilities

Thus, the above driving the decision to look into option to transfer vinyl into the digital domain, and the discussion of better to apply RIAA in the analog or digital domain stems from that.
In other words, transfer vinyl to digital has benefits over and above the advantage of possibly applying RIAA filtering in the digital domain.

I think useful to outline three different categories of LP listening/ digital conversion using XX and NOS DAC

1. Playing LPs (in real time) with ADC conversion in NOS1 and applying (real time) filtering in XX.
  The reason for vinyl analog to digital conversion is presumably to take advantage of XX digital filtering capabilities; if not for RIAA filtering, then room adjustment and/or x-over filtering. In fact, I see no real separation between digital room adjustment filtering and RIAA filtering. In other words, would it not be feasible for a system set up to use a digital room adjustment filter in XX to have two separate filters – one room adjustment filter for regular digital (CD) files and the second the same room adjustment filter with the RIAA curve imbedded (rather than two separate filters) for vinyl playback.
Also would be great to have NOS1 capability to pipe out the signal both in digital and analog simultaneously; i.e. while playing vinyl and listening to the NOS1 analog OUT signal, the NOS1 digital OUT signal could simultaneously be routed back to the computer and saved. This way, vinyl ripping would not be a separate chore, but a by-product of listening to LPs (optimal if option provided to save the digital file either with digital RIAA filtering imbedded or w/out RIAA adjustment, see below).     

2. Playing a digital file converted from vinyl, but stored on disc as a RAW file without imbedded RIAA filtering.
The file would be subject to digital RIAA filtering in XX when played. However, as the RIAA is not embedded in the file before storing on disc, playback of the file would benefit from continued improvements in XX digital RIAA filter capabilities. (Similar idea to RAW file format for photos).  Playback would require XX (for RIAA filtering), but not necessarily require use of NOS1 DAC.

3.  Playing a digital file converted from vinyl, and stored on disc as a file with RIAA adjustments imbedded (as a result of either analog or digital RIAA filtering).
As for any other digital file neither use of XX or NOS1 DAC strictly required.
However, would be great to have XX capability to upsample a stored 96/24 file to 192/24 and 384/24, the latter presumably requiring NOS1 DAC.

Bjorn

Bjorn, thanks. So, I was quite on the wrong track with my before post. Of course this is now only your opinion (and mine was just another), but assumed your opinion is shared by everyone (and I won't be playing vinyl anyway - not real time from the turn table at least), I rather want to make it myself more comfortable plus better (SQ) playback means;

In that case I'd indeed store the file raw, and apply the RIAA correction afterwards, like with the real time turn table playback. One big difference (and this is my conveniency and the bettr SQ), it then can be done as a preprocess and fits the general approach again.

At this moment I am not sure what it takes to store a raw take from vinyl, but notice it doesn't require XXHighEnd when other software exists for it. Key will be the "no RIAA correction" and the (digital) levels the file should be recorded in. This may be about necessary headroom (for the correction) and may not be an easy thing at all. I just don't know.
The downside will be the storage space it needs, and assumed 384 will be better than 192 (or 96) the files coming from it will be huge. Also, the preprocessing may take ages (you could try current 352.8 DXD (free) downloads from 2L to see what I mean (they can be played via XXHighEnd when you have a 176.4 capable DAC)).

Anyway, what is to do is :
1. Find the good way to capture non-RIAA corrected vinyl data;
2. Find RIAA correction software.

The latter may be convenient because I maybe can just use it. Its importance for now is though, that you can proove for yourself it works. When that has been proven I can build it myself via the (hopefully) known algorithms.
Both 1 and 2 above I won't be doing now, so others may. When something has been found we (I) will proceed on it. And yes, you will need a recording device to ever be able to try. So, if necessary I can try it, after someone found potentially good software (hey, I could do all in the end. Yes, AT the END haha).

If I'm totally off again, let me know ! (and I'm aware that I don't propose real time playback anymore)

Peter

[PeterSt]

Peter,
It is still not clear to me how I should connect the NOS dac to my computer.
Do I need to prepare my computer in some way (hardware, connections?).
I understand that I have still some time to do that 
Cheers, Eric. 

I want to know that as well.  I asked a few questions trying to get to the bottom of it but never really got a reply - which is quite understandable of course since it probably touches on proprietary information.  But as a potential customer I think we at least should know what we need to do at our end.  With the availability of powerful notebooks that incorporate I5's I have decided against a dedicated PC in favor of a notebook with a long USB cable connecting where I sit (or lie in my case because of my bad arthritis - but that is another story) to the USB dac.  From a convenience point of view this is a real plus and I would need one hell of a good reason to move away from it.

Thanks
Bill

Haha, nobody has to be afraid of not being able to connect to the DAC (says Scotty, kind of.). Therefore you don't need to know. Or at least not now. But in the end you will be knowing what you buy of course !

From a convenience point of view this is a real plus and I would need one hell of a good reason to move away from it.

No matter the i5, you don't know what you are missing. A bit difficult in your case, because you don't use XXHighEnd at all at the moment. But here are a few reasons :

• A notebook is underpowered. It always was, and it ever will, relative to desktops and the like.
  
  
• You *will* need all the power there is, no matter today it is two times more compared to one year back.
  
  
• Notice that this power is felt at nearly everything you do because of the preprocessing needed. The shorter that takes, the better it is. Always. And it will get more important when other preprocessing stuff comes around (xovers, room correction, be creative).
  
  
• There is no single means (at the moment) that can replace the speed of SATAII(I). Today you may be happy with an internal 500GB (by itself fast enough) disk, but in 3 years time (at the most) you will be in the same situation as many, and won't be knowing where and how to connect the disks. And if you do, a copy of one of them takes more than one day. This, while it can take 2 hours.
  
  
• When a notebook fails something (think in the area of glitches and the like) there is most often not more to do than throw it away. Better not be ignorant about this, because it just is so. Not so with a desktop etc. system, because virtually everything can be replaced.
  
  
• Similarly, this is all about SQ, SQ and more SQ, and a great deal of it comes from the components used. Now try to replace such a component for the better, in a notebook.
  
  
• Again similarly are your convenience options. Take the example from wimck. He bought (a new) system, but that system actually doesn't alllow him to use the HiFace. Allright, it is the fault of the HiFace, but still holds for useage. The solution was another USB controller. Try that with your notebook. And this is only one example, while dozens exist. Not today, then tomorrow (like the HiFace didn't exist "yesterday").
  
  
• Only very few things can be done with a notebook when it comes down to other OS versions. You'll need the version from the notebook manufacturer, or otherwise nothing will work. I know, these things can be done allright, but can you ? can everybody in general ? No, it is the other way around : virtually nobody can. With a notebook you are stuck in its shell.
  
  
• Apart from the underpowered thing, notebooks are slow. I wouldn't be able to work with them, because I really have better things to do than waiting for the notebook to come up with whatever it is it is doing in order to get whatever it is to be done, done. You may not recognize it, because you don't know better (just used to it), but take it from me a todays notebook is still way more slow than a normal desktop from 10 years back.
  
  

So where does this leave you for conveniency ?

You best option (I think) is to get yourself a nice flatscreen, a couple of lengthy PS2 and VGA (or DVI) cables. Drop your screen, mouse and keyboard at the place you want (which is not on you lap in my ideas) and let your music PC be as large as needed, and even close to the stereo (so you can use an USB cable (etc. !) of normal length instead of something which implies bad SQ (in theory)).

A second best option is a laptop connected by Wifi to ANOTHER PC in the same network, that PC ethernet connected to the music PC (never stuff Wifi in the music PC !). The laptop controls the music PC my means of RDC. Notice this already will degrade SQ because of the RDC activities in the music PC.

A third best option is a laptop which also controls the main machine by means of RDC but is connected by ethernet directly. This is third because less convenient, and will degrade SQ as much (whatever much means) as the before option.

So, IMO there are a hell of a lot of reasons enough to change things a bit. You do want the best sound, right ?
Peter

[bgjohan]

Peter

Converting vinyl to digital and digital RIAA filter

1. Digital RIAA filter plug-in
see, free download (VST)
http://www.kvraudio.com/get/3550.html

2. Saving files
My thought was to record and save vinyl as 96/24 files.
As for upsampling in XX, I suppose upsampling of 96/24 files will require a 32 bit DAC, such as NOS1 (similar to upsampling of 16 bit files requires a 24 bit DAC).

Bjorn

[listening]

Hi Bjorn, hi Peter,

there is not only one RIAA curve. As implemented by behold company there are "RIAA, RIAA (IEC), TELDEC, AES, Columbia LP M33, NAB,
NARTB and London M33+M45". This is the only product I know which should be near your wishes Bjorn --  http://www.behold.eu/page.php?en32118 --.

Georg

[PeterSt]

Hi Bjorn, thank you.

On the Saving Files :

First off, personally I wouldn't capture at 24/96 and think it's best to upsample to 192 next. Then I would capture in 192 ...

Next, you are right that upsampling from 24/96 to 192 requires more bits officially (actually, 1 bit more in this case), but I wouldn't bother about that at all. There is nothing to perceive from even 24 bits hence from the dynamic range that brings. It is just way too large already (144dB).

If you wonder how or why, I have written more often about it. Maybe you can find it (I'd search for "dynamic range", "24 and "32" at the same time). And otherwise maybe open a new topic for it ?

Notice that the NOS1 is 24 bits, but that the output to it is 32 bits (even at 768). Here too, 32 bits would bring nothing useful !

Regards,
Peter

[PeterSt]

Georg - But isn't it so that there are more of those curves allright, but only one is RIAA ? ... and *that* is the one used the most if you're only not playing vinyl from before the 1950's or so ?

Also, I think I have read that what was used before a certain year is unknown anyway, so we wouldn't know how to "recurve" it. As your phono stage can't ...

But I don't know much about it !
Peter

[listening]

Hi Peter,

that's right - starting from that time (sometimes with a delay of months or years) there was one type of the RIAA curve standard. But a lot of the good records are pressed on vinyl before  But there is a cutting machine at the end of the process, mostly Neumann cutting machines. They invented another cutting time constant (50 KHz roll-off) which is part of most newer LP's. It is implemented in the aquvov phono preamp -- http://www.aqvox.com/phono.html --

Georg   

[audiodesignguide]

Peter,
the schematic is private or public ?

Have you used a design like this one?
http://tech.juaneda.com/en/projects/digitaldecoder.html


Andrea Ciuffoli
www.audiodesignguide.com

[PeterSt]

Andrea,

I looked, but no. I don't see any resemblence. The 1704 maybe, but there it stops.

Btw, that is not allowed to be used commercially, but I guess you knew that.

The design is proprietary (and owned by me).

I hope this answers your questions !
Peter

[audiodesignguide]

Do you seel the dac pcb board ?

Any simplified schematic is available ?

Andrea Ciuffoli
www.audiodesignguide.com

[PeterSt]

Andrea,

You wouldn't be able to do anything with the DAC board, so the answer is No for already that reason.
Estimating correctly what you want to do with it (I searched my life out of me at the time), it won't work. The whole thing comprises of elements all not done before, so it is a consistent whole, no part being able to work without the other.
You might just as well start from scratch yourself ... I did that in the end (by kind of accident) ...

Thanks,
Peter

[audiodesignguide]

Peter,
Are this design able to play at 192KHz 24bit ?

There is No bit shift, no digital filter and No oversampling

The PCM63 are changed with PCM1704

[PeterSt]

Hi again Andrea,

So ... in my earlier post I said I estimated what you were up to. Now please allow me to ask you ...

?

Peter

[Telstar]

Hi again Andrea,

So ... in my earlier post I said I estimated what you were up to. Now please allow me to ask you ...
?
Peter

I think he wants to build a cheap 2ch NOS dac able to play highres material.