[isquirrel]

   
Even though you are already comparing state of the art gear against the Nagra and as you like the Nagra for more reasons than just SQ, I think you owe it to yourself to also audition a TotalDac.  It's creator, Vincent Brient, is a brilliant guy with an interesting engineering background that makes him well suited to doing what he does and unlike some other companies, DACs are all he makes and he hand makes each one using very expensive 0.01% tolerance Vishay Foil Resistors (and not the cheaper 0.1% or even 1% variety) that many consider the finest resistor there is.  Even with the less expensive d1-dual, my sense is it will compete well with the Nagra and for directly driving an HE-1000, it may even outdo the Nagra.  You cannot underestimate it based on price (even though 9,100 Euros is not cheap) because Vincent Brient sells directly whereas with Nagra, MSB and others, you have to pay a dealer and so the price you pay is inflated.  Should you wish to aim higher, he makes a d1-monobloc with 400 Vishay Foil Resistors all the way up to his flagship, the d1-twelve which contains an unheard of 12 ladders or 600 Vishay Foil Resistors for about the price of a dCS Vivaldi.  With his equipment, the price you pay actually goes towards something since he doesn't have to pay a big staff (he is a one man show). Vincent is so confident of his products that he will give any customer 14 days to audition his items and will take them back without question and without a restocking fee if you're not satisfied (although you would be responsible for shipping).  He is also very responsive and patient to answer numerous questions via e-mail.  During your next visit to Europe, you should strongly consider a visit as we would all value your impression on this DAC given your vast knowledge of so many fine DACs.

A quick correction, I do not have the Nagra yet, hopefully this time tomorrow night. My interest in the Nagra is as I said earlier in the thread is primarily because they have gone a whole step further and attacked the very manner in which the files are played back in software. Other DAC manufacturers are as you point out improving the topology of the DAC but the in most cases the file is not reconstructed to the same extent as Nagra + Andreas Koch are doing. One thing iOS for sure we will find out if they have succeeded. My ears pricked up when I read how they considered the timing playback methodology to be a critical component. I see Music Servers becoming increasingly popular and recognised for their importance.
 
The source is the music and how it is recorded, I have recordings that are PCM and yet sound better than high res examples of others. Next down the line is the streamer/laptop or Transport, the more noise and in a Transport's case the more mechanical errors then there will be errors in the bitstream. 
 
Jitter is time based error.  There are many factors that can increase jitter error and high frequency noise is an area that is overlooked by many designers.
 
Noise is the cause of jitter at its most basic level. The old argument that zero's are zero's and therefore USB cables, Transports and DAC's don't matter is completely ignoring the basic fact that the bitstream is carried in the physical domain so with the introduction of any mechanical and or other noise (power supplies etc etc) then the bitstream will not be read correctly and there will be errors. There is no such thing as a perfect bitstream. Various methods have been tried to overcome this including up sampling, different filters etc but that's all messing with the bits and I have found over the years that NOS DAC's tend to sound less mechanical and more natural.
 
DAC technology will continue to evolve at a steady pace, new innovations such as Meridian's MQA address the issue of noise at the root level so are more likely to offer major advances than DAC tech. You only have to look at Turntables and see the continued evolvement of a technology which is now quite mature and you can see how far they have come in the last 5 years. 
 
The biggest single change in how audio companies are addressing technological advances is in the field of damping, vibration control and high frequency noise reduction. Power supplies and the accuracy of the clocks are also dominating the current thinking of Streamer & DAC designers.
 
All this is in an attempt to reduce the ear/brain perception of timing errors. We still do not understand exactly how this works and perhaps we never will. Some people believe that time based errors are more noticeable to the human ear than frequency based. The DAC's I hear that are sounding better, do so because they are sounding more realistic, analog like if you follow that we are not a digital species. The only advantages digital has over analog is the easy transport and distribution of material, dynamic range and S/N ratio. So when I see a DAC designer who has worked to improve his products power supplies and reduce internal electrical noise that is inherent in digital to analog conversion, this is a good thing. This noise is very high frequency and is very destructive, people think that its best if DAC's are shielded from External noise but the opposite is true it is other components that needs shielding from DAC's 
 
Suggested good reading is Bob Stuart (Meridian) white paper re MQA as he gives a very thorough but technical explanation of where he see's DAC/digital design going in the future.

 

[bmichels]

Very interesting but then, IF Meridian's MQA is the next big improvement, then should we invest NOW in a 20.000 DAC (Nagra, TotalDAC Mono...) that may never be able to support Meridian's MQA and thus becomes "obsolète" sooner than expected ?

 

[isquirrel]

MQA can be implemented on a file based level, software playback level and or most effectively a DAC firmware level. Most DAC's are firmware upgradable so we should be pretty safe. Bob Stuart has worked to make sure that we all get the benefit, the degree of that is up to the engineering of your playback systems capabilities and the DAC manufacturers willingness.

 

[Articnoise]

I agree with Klonk. A very interesting thread, so much useful inputs from experienced headfiers.

 

I also have an OT question about connecting headphones directly into the balanced outputs of the DAC. Does it matter if the output on the DAC is tube based? If one for example is going to use a tube speaker amp it has been recommended to put resistors in parallel to better match the low impedances and to save the headphone or amp from blow up. The output impedance of the DAC is the opposite and much higher (300 Ohms), so my question is will it be safe to connect headphones directly to a tube DAC. My DAC has an implemented pre and can deliver more than 6v balanced. I don’t know if this matters; but the analog tube stage is automatically switching off by relays after a few seconds if no music is playing and then switch on again then playing. TIA

 

From the manual:

 

Output Impedance: 300 ohms balanced. It can drive a balanced impedance of 20K ohms or higher.

 

Recommended Load > 20Kohm balanced, >10Kohm Single-Ended.

 

[JaZZ]

Does the Nagra have an extra amplification stage for the headphone output or is it directly coupled with the DAC's (line) output, as with the Hugo (TT)?

 

[bmichels]

Does the Nagra have an extra amplification stage for the headphone output or is it directly coupled with the DAC's (line) output, as with the Hugo (TT)?.

I think It has a dedicated Amp. And I was officialy confirmed that it makes good use of the vacum tube

 

[Johnny Moondog]

  Well hopefully you will be able to draw some safe conclusions from the results of my testing. The Nagra will be compared to the Gryphon Kalliope which betters every other DAC I have compared it to, including the 4 box dCS Vivaldi stack (there were 3 of us to witness it and we were all genuinely shocked), the Trinity DAC, MSB Analog DAC with base, Audionote DAC 5 Signature.

 
I look forward to reading about your test. For about 5 minutes I actually considered inviting myself to fly out from San Francisco to join your group! But thankfully my sanity returned.

 

[Johnny Moondog]

  AHHH you also tested the Trinity DAC !  I never understood how they can justify it's pricing ! what did you think of it ? 

 
As a proud member of Audiophile Anonymous, I actually booked a flight from San Francisco to New York City to audition a Trinity DAC. The opportunity then disappeared when Trinity's dealer changed and they were remodeling the showroom while I was visiting NYC.

 

[Johnny Moondog]

  I generally divide equipment and listeners into 2 camps, those that prefer neutrality and detail and to feel that they can hear everything, and those that are naturally drawn to musicality and tonal warmth and don't mind sacrificing a bit of that in your face detail.
 
[...]
 
For me the Trinity DAC falls into the 1st camp, neutral, dry and plenty of detail...
 
[...]
 
The dCS and the Trinity have a similar sound. I think the Trinity is superior to the dCS. I was really shocked by the dCS performance... 

 
What fun "relief" to read your thoughts. I remember an audition of a dCS DAC and sitting there thinking... "Huh? What? This is THE dCS? What's *obviously* wrong with me?"
 

...what I am most interested in with the Nagra above all the others, is that by using a genius like Andreas Koch, Nagra are getting at the fundamental issue of how best to decode the data.

 
This is exactly what captured my curiosity when I first read about the research and development that Nagra explored.

 

[isquirrel]

Its on its way, as a proud member of the above club - I organised same day pickup (even though its in a different State), will be delivered at 2.00 in the morning 

 
 

 

[paulchiu]

OMG.  I am so horny looking at these boxes.  I am so envious, and excited.  Going for a glass of wine.
Wondering when mine will arrive.
 
 
 
Quote:

  Its on its way, as a proud member of the above club - I organised same day pickup (even though its in a different State), will be delivered at 2.00 in the morning 

 
 

 

[romaz]

I do not understand why we do not have the same issues with DACs driving Headphones direct ?

Indeed DACs are also designed to drive High impedence Pré or Amps ! Not dedigned to drive low impedence Headphones !!

Here's the difference as best as I can explain it.  When a DAC is sending a signal to a pre-amp or amp, it is a line level signal.  When a DAC (or amp) sends a signal directly to headphones or speakers, it is not a line level signal but a power signal.  For line level signals, it is not important that the output component (DAC) transfers maximum power to the input component (pre-amp or amp) because ultimately, the amp can turn a weak signal into a much stronger signal.  The key is that the signal is transferred efficiently and with high integrity.  If not, you get potential timing and SQ issues (echoes, colorations, etc).  This efficient transfer is best achieved if the input component (pre-amp or amp) has an input impedance much higher (at least 10x) than the output impedance of the output component (DAC).  In other words, the more load the DAC sees as it transfers a line level signal to a pre-amp or amp, the better it is for the sake of sound quality.
 
With power signals, while signal efficiency and integrity has its place, the only thing speakers or headphones care about is the power it receives.  Here, impedance matching is much more important because maximum power is transferred when the impedance of the output source equals the impedance of the input source.  For example, If you have an 8 ohm speaker, the output impedance of your amplifier ideally should be 8 ohms.  If the impedance of the speaker or headphone is higher than that of the amplifier, what you get is less power but everything should still work fine.  Drive a 16 ohm speaker with an 8 ohm amp and it sounds quieter but generally, it sounds fine.   
 
The bigger problems occur if the input impedance of the input component is lower than the output impedance of the output component.  With line level signals, if the input impedance of the preamp or amp is lower than the output impedance of the DAC, what you usually get is audible distortion and possibly damage to certain types of DACs (especially tube DACs).  With power signals, if the input impedance of a speaker or headphone is less than the output impedance of the amp, your amp has to work harder and you risk burning out your amp.  If you have a tube amp, it could catch on fire.
 
Tube DACs or tube preamps are known to have very high output impedances whereas solid state amps can potentially have low input impedances and so if you are not careful and you pair a tube DAC or tube preamp with the wrong kind of solid state amp, you could blow up your tube DAC/preamp (not literally but it could catch on fire).  This applies to headphones, too!
 
I hope I have explained this adequately.  Some things have been oversimplified.
 
While I don't know the output impedance of the Nagra (in fact, it's very disappointing that there are so few specs on this DAC available to the public), the output impedance of the TotalDac is 18 ohms.  As long as you drive headphones higher than 18 ohms, you should get good results and I have verified this with Vincent.  My experience with the HE-1000 which is rated at 35 ohms is that it sounds just fine directly connected to the TotalDac.

 

[romaz]

 
I never touch the music server save to insert CD for ripping. I start the iOS app on my iPad and browse my music and what Tidal has to offer. If my iPad is being used elsewhere I simply start the Mac OS X app and do the same thing from there. COuldn't be simpler or more enjoyable. There is nothing to fiddle with in Roon re SQ and I have no use for any other 3rd party audio endpoints like HQ Player, I prefer to let DAC's of this quality handle the files. I have an automated back clone running every morning on the entire music drive to Raid 5 NAS. I keep all my music files locally as they sound better that way. My CAT is configured with 3 SSD server class drives. One for the OS and other 2 for music files. CAD have pre-nsyalled and configured Team Viewer which makes support if needed simple.

 
This is my kind of system.  I have been exchanging e-mails with Scott and I have an ideal configuration in mind similar to yours.  He verified for me Roon can be set up.  Pricing is also competitive with the Aurender N10.  My question for you is do you believe the SQ out of the CAD is significantly better and not just a little better than the N10?  Hard to believe because the N10 sounds incredible.

 

[romaz]

I think It has a dedicated Amp. And I was officialy confirmed that it makes good use of the vacum tube

It sounds like if you use the Nagra only for headphones via the headphone port, much of it goes to waste.

 

[isquirrel]

   
This is my kind of system.  I have been exchanging e-mails with Scott and I have an ideal configuration in mind similar to yours.  He verified for me Roon can be set up.  Pricing is also competitive with the Aurender N10.  My question for you is do you believe the SQ out of the CAD is significantly better and not just a little better than the N10?  Hard to believe because the N10 sounds incredible.

This is the problem when dealing with high end components, they are all good, subjectively I might prefer one and you might prefer another. You will have to find out which works for you. Obviously I prefer the CAD I also know the underpinnings which I am not at liberty to discuss. My research and Scott's parallels as does our taste in sound. CAD have a 30 day money bank guarantee so you will be safe if you don't like it. I have just bought another one for my 2 channel system.