REVIEW: Comparison of 5 High End Digital Music Servers - Aurender N10, CAD CAT server, TotalDac d1-Server, Auralic Aries, Audiophile Vortex Box
Mar 11, 2016 at 11:32 PM Post #301 of 1,483

REXNFX

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Yes, I sat through the MQA demo in Las Vegas at CES in January and it was impressive.  More than serving as a compact wrapper to allow streaming of hi-res files, it attempts to compensate for the ringing artifacts caused by the ADC but it's becoming clear that decoding has to occur at the DAC and not the server for this technology to work its best.  It is also not as simple as a firmware upgrade for the DAC and so widespread adoption of this technology is not a given.  I was initially quite optimistic that this technology will be the future, now my optimism is more guarded.  

Moreover, while MQA attempts to correct for the sins of various ADCs, it seems to me that it is a band-aid approach and that creating a better ADC so that the DAC doesn't have to try and compensate for it would be the better solution and this is what Chord's DAVINA project is attempting to do.  Given how successful Rob has been with the DAVE, I am more optimistic about this solution.  Its key to success will be how widely it is adopted but if the benefits are heard with all DACs (of course, the DAVE will benefit the most), then it may be the better solution.  

If you are interested in hearing how the different bitrates of the same recording sounds in your system, from MQA to 16/44 to 32/352 to DSD256, here's a link you might be interested in.  With the DAVE, since the music server no longer seems to matter, the focus now shifts to the quality of the digital file.

http://www.2l.no/hires/

The thing I always come back to is some of my favourite LP's were recorded digitally so I think the recording technology was fine but poorly implemented in most cases.
 
Mar 12, 2016 at 3:30 AM Post #302 of 1,483

Articnoise

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  I don't mean to discredit any other DAC manufacturer, including MSB or otherwise.  MSB makes very fine products and I hold them in high regard.  When I made that statement, it was meant to reflect my opinion that if you value transparency, then "direct to DAC" is the best way to achieve it and so in this regard, I would choose even the TotalDac d1-single (direct to DAC) over just about any other DAC where you have to use a headphone amplifier.
 
You can stack digital components and potentially not impact transparency but the more components you stack in your analog chain, transparency will be impacted.  Even the lowest impedance interconnect will add its signature to the sound.  Same thing goes for speaker or headphone cables, crossovers and transducers and so the less parts in the analog chain, the better is the rule.  Those who think their amp is transparent is fooling themselves.  Look at the bandwidth, noise floor, dynamic range, THD, etc of the finest amplifier and it will pale in comparison to the identical characteristics of a great DAC and I have felt strongly about this for a while now, even when I owned my TotalDac.
 
Regarding the Select II, I am aware of MSBs statement that it can be adapted for "direct to DAC" connection with certain headphones and hopefully, they develop this feature fully.  I'm not sure if MSB themselves are aware of how good a "direct to DAC" connection can sound because they cater more to 2-channel then headphone use.  Because the output impedance of the Select II is high (about 75 ohms if I recall correctly), it will work well for something like the LCD-4 or HD800 but no so well for lower impedance planars like my HE-1000.  That is what is unique about the TotalDac and the DAVE, their output impedance is low enough to drive just about any headphone or IEM.  The main limitation is gain.  For some who prefer headbanging volume levels with their Abyss or HE-6, neither the DAVE nor TotalDac may have enough gain but having heard the Abyss on the DAVE, I will say that this direct connection to the DAVE is the best that I have ever heard the Abyss.
 
I am presently using a Sonore Sonicorbiter SE as my source because it is inexpensive ($300), small, runs Roon smoothly and it gets the job done but in truth, with the DAVE, almost any source will get the job done as long as it can deliver a bit-perfect file.  Even a basic Aries Mini, cheap $50 CD player, Sonos, Chromecast or Roku box has the potential to sound as good as an Aurender W20 or $20,000 Esoteric CD player with the DAVE.  I am unaware of any other DAC that can make that claim.  I don't know how prevalent the DAVE will become in head-fi.  It is, after all, a $13K DAC but this piece of equipment has the potential to completely transform how most of us think about system setup and tuning.

 

I interpret it as you haven’t heard the MSB Select.

 

Hum, pretty strong statement to say that “those who think their amp is transparent is fooling themselves.” First of all, many/most people (if they have to choose) prefer a harmonic distortion to non-harmonic distortion. Second the THD, dynamic range, etc. from a good amplifier is much better than for example the Abyss or HEK. Yes I agree that it is always better with an as clear signal as possible upstream, but the end result will not be like the best part in the audio chain, it will be the worst. The rule is, an audio setup is never better than its weakest link and everything matters.  

 

I do understand and believe in the benefit of headphone direct out and that it can result in better transparency, if everything else is equal. I also agree that transparency is very important, but far from the only aspect am looking for in an audio gear. Other important qualities that a good DAC/amp/transducers should provide are good drive, deep firm bass, natural and organic sound, 3D soundstage, precise image, inner details, black background etc etc.   

 
Mar 12, 2016 at 10:35 AM Post #303 of 1,483

romaz

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I interpret it as you haven’t heard the MSB Select.

 

Hum, pretty strong statement to say that “those who think their amp is transparent is fooling themselves.” First of all, many/most people (if they have to choose) prefer a harmonic distortion to non-harmonic distortion. Second the THD, dynamic range, etc. from a good amplifier is much better than for example the Abyss or HEK. Yes I agree that it is always better with an as clear signal as possible upstream, but the end result will not be like the best part in the audio chain, it will be the worst. The rule is, an audio setup is never better than its weakest link and everything matters.  

 

I do understand and believe in the benefit of headphone direct out and that it can result in better transparency, if everything else is equal. I also agree that transparency is very important, but far from the only aspect am looking for in an audio gear. Other important qualities that a good DAC/amp/transducers should provide are good drive, deep firm bass, natural and organic sound, 3D soundstage, precise image, inner details, black background etc etc.   

I have heard the MSB Select II and I have already posted my very favorable impressions of the MSB Select II but as I stated, it was not my intent to bring MSB or any other DAC manufacturer into this.
 
http://www.head-fi.org/t/613387/msb-analog-dac-review-p3/510#post_12238087
 
As to any amp impacting transparency, I fully stand by this statement.  If you prefer to have your amp serve as a tuning aid, there's nothing wrong with that, but that's a separate matter.  It's like adding salt and ketchup to your omelette, it may not be what the chef intended but it's certainly your prerogative.  I have never been to a symphony or to a concert and wished to myself that there was more bass or better inner detail or more dynamic range.  In the same way, if you have a good recording and if your DAC is faithful to render it, I have not found it necessary to alter it.
 
 As to natural and organic sound, 3D soundstage, precise image, inner details, black backgrounds, do you really think an amp can provide these things better than a good DAC because those parameters are more the responsibility of the DAC than the amp?  In a digital system, the analog signal starts at the DAC.  The best that a component that follows the DAC can do is to be invisible if transparency is your goal but as I stated, any analog component will have a signature.  The DAVE has a noise floor of -180dB.  No amp comes close to this.  It also has a measured THD of 0.000015%, probably 500x better than an amp.  Noise floor modulation, small signal linearity, bandwidth...I can go on.  
 
What amps provide that a DAC by itself cannot in sufficient quantities with certain headphones is gain.  The DAVE (and even my TotalDac), for example, can drive an Abyss extremely well but only to a point but until that point, drive and bass are all there.  With very high dynamic range music, such as Tchaikovsky's 1812 overture, I have caused the DAVE to clip at full gain as the canons go off in the end.  Also, if you prefer to listen to the Abyss (or HE-6) at headbanging levels, you will want an amp.  If you love the bloom of a certain tube or wish to compensate for the overly clinical nature of your headphone, well, amps can helpful but again, we are no longer talking about transparency.
 
Mar 12, 2016 at 12:01 PM Post #304 of 1,483

romaz

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  Second the THD, dynamic range, etc. from a good amplifier is much better than for example the Abyss or HEK. Yes I agree that it is always better with an as clear signal as possible upstream, but the end result will not be like the best part in the audio chain, it will be the worst. The rule is, an audio setup is never better than its weakest link and everything matters.  

I just caught your point on this and I agree with you, the headphone can be the weak link and connected directly to the DAVE, it is the weak link (along with the headphone cable), however, many who have compared headphone direct to DAVE vs headphone connected to amp connected to DAVE can very easily discern the drop in transparency when an outboard amp is connected to the chain.  Despite the limitations of my HEK, HD800 S and even my TH-900, the difference is very evident.
 
With my DAVE now, I am using it for both headphones and 2-channel and even with my speaker amp, the finer qualities of the DAVE shine through and so I'm not suggesting amps have zero transparency, I'm just suggesting they are not as transparent as DAC-direct.
 
Mar 13, 2016 at 7:54 AM Post #305 of 1,483

Articnoise

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  I have heard the MSB Select II and I have already posted my very favorable impressions of the MSB Select II but as I stated, it was not my intent to bring MSB or any other DAC manufacturer into this.
 
http://www.head-fi.org/t/613387/msb-analog-dac-review-p3/510#post_12238087
 
As to any amp impacting transparency, I fully stand by this statement.  If you prefer to have your amp serve as a tuning aid, there's nothing wrong with that, but that's a separate matter.  It's like adding salt and ketchup to your omelette, it may not be what the chef intended but it's certainly your prerogative.  I have never been to a symphony or to a concert and wished to myself that there was more bass or better inner detail or more dynamic range.  In the same way, if you have a good recording and if your DAC is faithful to render it, I have not found it necessary to alter it.
 
 As to natural and organic sound, 3D soundstage, precise image, inner details, black backgrounds, do you really think an amp can provide these things better than a good DAC because those parameters are more the responsibility of the DAC than the amp?  In a digital system, the analog signal starts at the DAC.  The best that a component that follows the DAC can do is to be invisible if transparency is your goal but as I stated, any analog component will have a signature.  The DAVE has a noise floor of -180dB.  No amp comes close to this.  It also has a measured THD of 0.000015%, probably 500x better than an amp.  Noise floor modulation, small signal linearity, bandwidth...I can go on.  
 
What amps provide that a DAC by itself cannot in sufficient quantities with certain headphones is gain.  The DAVE (and even my TotalDac), for example, can drive an Abyss extremely well but only to a point but until that point, drive and bass are all there.  With very high dynamic range music, such as Tchaikovsky's 1812 overture, I have caused the DAVE to clip at full gain as the canons go off in the end.  Also, if you prefer to listen to the Abyss (or HE-6) at headbanging levels, you will want an amp.  If you love the bloom of a certain tube or wish to compensate for the overly clinical nature of your headphone, well, amps can helpful but again, we are no longer talking about transparency.

 

The function of an amplifier is not to be a “tuning aid”. What an amp is supposed to do is amplifying a weak audio signal coming from the source to a stronger signal which headphones or speakers can operate with (this is often done in more than one step). If the amplifying is done in the DAC or in separate amp has both its pros and cons. The pros is less is more in hifi. The cons are usually less driving force and that noise from one section easier can interfere negatively on another section. Most of the better hifi gear are made in separate units or separate sections to prevent noise pollution and heat interference between different parts. The higher the power and heat the more separation and isolation to other parts is needed. The function, to amplify, is the same no matter if it take place in a gear that is called a DAC or an amp.

 

I feel that I have to point out two things. The Hugo is operating in the same manner as the Dave and many of the benefits that are stated for it are the same. Yes I know you didn’t hold it in the same high regard as some others, but the pros of less is more and the adding of a dedicated amp is the exact same. As is the theory that all a separate amp is bringing to the table is adding coloration. Nothing about better grip on the transducer, blacker background, more dynamic, firmer bass etc. Don’t get me started on the proclaimed sound of tubes. Second the THD, DR etc. on Dave is not measured at full load with headphones. Maybe they are still good, but they will be affected negatively the more it is pushed.   

 

“As to natural and organic sound, 3D soundstage, precise image, inner details, black backgrounds, do you really think an amp can provide these things better than a good DAC because those parameters are more the responsibility of the DAC than the amp?” The short answer is yes! The Hugo was not my cup of tea, to lean and not enough drive for even the LCD 3/Hd800. I have also asked one person who owns the Totaldac D1 how it sounds direct out with HD 800 compared to use the Master 9 and the answer was not a big difference, a bit better clarity and a bit less liveliness.   

 

Don’t get me wrong I do find Dave to be a very interesting DAC/amp and I definitely will hear it then I get an opportunity. The ability to drive a headphone direct from the DAC/amp is a nice future if it can provide the same amplifying capacity of a good standalone amp, including good tuning and driving force etc etc. The “immunity” to the quality of the source gear and digital cables is another attractive aspect.

 

 

 

 
Mar 13, 2016 at 4:18 PM Post #306 of 1,483

romaz

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Due to some glitch, my post got cut off before I finished it and so I have reposted it as I intended it in post #308.
 
Mar 13, 2016 at 4:35 PM Post #307 of 1,483

smial1966

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Now that made me laugh out loud. As MSB are touting 6000 taps as being amazing and yet DAVE has 164,000 taps, which in MSB parlance would probably equate to divine intervention by the God of audio. Incidentally, is there a God of audio and/or hearing?!?
 
Mar 13, 2016 at 4:53 PM Post #308 of 1,483

romaz

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  The function of an amplifier is not to be a “tuning aid”. 

 
Yes, this is my point exactly yet those who look for their amplifier to provide them their desired harmonic distortions are using it exactly for that reason.
 
 

If the amplifying is done in the DAC or in separate amp has both its pros and cons. The pros is less is more in hifi. The cons are usually less driving force and that noise from one section easier can interfere negatively on another section. Most of the better hifi gear are made in separate units or separate sections to prevent noise pollution and heat interference between different parts. The higher the power and heat the more separation and isolation to other parts is needed. The function, to amplify, is the same no matter if it take place in a gear that is called a DAC or an amp.

 

 
No disagreement here.  If you need gain, then you need gain.  For 2-channel, this is a must.  For certain headphones, you can get away with not having to add gain switches to the DAC but as soon as you do, you will lose transparency.  That is an incontrovertible truth and "transparency" has been the focal point of my initial statement all along, not personal preference.  As to separation and isolation being necessary because of heat, yes, this is true.  In the past, I have always looked down on anything with integrated power supplies.  As a rule, I have always preferred "separates" as opposed to "integrated."  The DAVE is different.  It does not get appreciably hot.  Rob has done a marvelous job with isolation with the DAVE.  You really need to hear it.
 
  I feel that I have to point out two things. The Hugo is operating in the same manner as the Dave and many of the benefits that are stated for it are the same. 

 
Good points here.  That is the curse of the DAVE is that people assume it is like the Hugo. As you've stated, I have never been a fan of the Hugo and assumed the DAVE would basically be like a Hugo on steroids.  It couldn't be further from the truth even though they share similar DNA.  The Hugo has 26,638 taps while the DAVE has 164,000 taps.  The Hugo has a 5th order noise shaper with -240dB of performance while the DAVE reaches down to -350dB which is a giant chasm as this isn't linear but logarithmic.  The Hugo was designed to come in at a certain price point.  With the DAVE, the only goal was ultimate SQ and Rob threw everything he knew into it.
 
Before you start to think these terms apply only to Chord DACs, here is what MSB has to say with their current DAC V and Analog:
 

MSB Digital Filters

MSB has developed a series of digital filters that are optimized for the incredibly accurate DACs we make. We have 4 filters we have available in the DAC V and Analog DAC. The MSB filters are custom DSP based Digital filters. The sine x function is the ideal shape to apply to the audio filter task, but unfortunately to work perfectly it must sample an infinite number of samples. Our 16x filter contained 3200 taps, a very large sample and works well. The 32x Filter contains an amazing 6000 taps, and the increased size of the filter more closely approximates the ideal filter. Immediately you can hear the increased clarity of the music.

Noise Shaping = Less digital Graininess

MSB has applied noise shaping technology, not directly to the audio as SACD and Delta Sigma DACs do but to the actual digital filter. This novel approach reduces that digital harshness without loss of detail or focus.

Unfortunately, MSB doesn't provide the performance of their noise shapers.

 
Quote:
  As is the theory that all a separate amp is bringing to the table is adding coloration. Nothing about better grip on the transducer, blacker background, more dynamic, firmer bass etc. Don’t get me started on the proclaimed sound of tubes. Second the THD, DR etc. 

 

 
No, I never said this.  As I stated, amps are necessary for gain but an outboard amp, as with any analog component after the DAC, will add coloration, some more than others.  Even the type of glue used for your speaker cones has been shown to add coloration.  If transparency is the goal, then you do what you can to minimize these colorations.  As to better grip, which I define as control, some outboard amps provide better grip than others, I think most of us have experienced this but an amp will not have better control than the DAC because no amp can match the speed and agility of a DAC.  The higher the gain your amp provides, the slower the speed and the less the agility is the rule.  Even the best electrostatic amp can't outdo the speed of a DAC, the best it can theoretically do is match it.  Blacker background, I already addressed this.  Look at the noise floor of your favorite amp if it is provided and it will not come close to a DAC.  If it isn't provided, look at THD (which is another measurement of the noise that your amp produces) and it won't even be close.  Regarding "dynamic", if you're talking about gain, yes, an amp can produce a louder sound but as far as dynamic contrasts or dynamic range, they probably won't be close.  The DAC will win or else the amp could be as good as the DAC but never better because the DAC is the originator of the signal.  You can't outdo the original.  As far as firmer bass, if you mean enhanced or artificial bass, yes that is a coloration that an amp or transducer can provide but that doesn't mean it's real.  As to tighter bass or better bass definition, again DAC wins because it comes down to control.  Again, the signal begins with the DAC.  An amp can alter the signal and maybe alter it to your preference but it will be at the cost of transparency.  It's like saying the original Star Wars wasn't so good and that you could write a better version of it.  Well, guess what?  That's how George Lucas wrote it and while you can re-write it if you wish, then it would no longer be Star Wars.  But this brings up a good point, if you don't have a good recording to start with, sometimes it is necessary to add tuning but that is not the fault of the DAC.
 
 

Dave is not measured at full load with headphones. Maybe they are still good, but they will be affected negatively the more it is pushed.   

 

 
It is still that good.  The unique thing about the DAVE is it has no measurable noise floor modulation, something that cannot be said for the Hugo or any other DAC or amp.  Here is what Rob had to say:
 
"Now the really unusual thing about Dave is the residual noise (no signal) is 2.6uV, THD and noise at -60dB is still 2.6uV, and THD and noise with 2.5v OP is still 2.6uV. This completely unvarying result is remarkable for any analogue device, let alone a DAC/amp. This measurement is more telling, as it relates to sound quality, as the smallest amount of noise floor modulation is very audible, in terms of things sounding harder and less smooth."
 
Before I move on, pay attention to the fact that noise with the DAVE is measured in uV and not millivolts, which is how most audiophile amps are measured.  And this insanely low noise doesn't worsen as you increase gain.  This represents a difference of 1000 fold.  Talk about black background.
 
  “As to natural and organic sound, 3D soundstage, precise image, inner details, black backgrounds, do you really think an amp can provide these things better than a good DAC because those parameters are more the responsibility of the DAC than the amp?” The short answer is yes! The Hugo was not my cup of tea, to lean and not enough drive for even the LCD 3/Hd800. I have also asked one person who owns the Totaldac D1 how it sounds direct out with HD 800 compared to use the Master 9 and the answer was not a big difference, a bit better clarity and a bit less liveliness.   

 
Then we agree to disagree.  Again, if you are using the Hugo to decide how the DAVE sounds, then I can see why you think the way you do but I can assure you, they're not the same.  Not even close.  As to the person you spoke with who owns a TotalDac d1, people will have their own opinions and if they prefer one presentation to another, that's fine.  Having been a TotalDac owner and having compared the d1-single to the d1-dual to the d1-monobloc, while they each have the trademark TotalDac richness in tonality, as you go up the chain, what you glean more of is space and air.  You go from 2D to a more 3D presentation with finer layering of details.  If the person you spoke with was using a d1-dual using the headphone port in the back, that connection, while direct, uses only half of the resistors of the DAC amounting to listening to the d1-single which has a flat 2D sound compared to d1-dual via balanced XLR outputs and especially compared to the monobloc that I owned.  The DAVE goes even further than the monobloc.  I can assure you, as you go up the TotalDac chain and eventually to the DAVE, this direct-to-DAC connection results in a greater degree of depth and realism.  Regarding the HD800, while this headphone presents a very wide soundstage, there is not much depth, at least compared to my HE-1000.  As I'm currently comparing my new HD800S to my HE-1000, this is what I'm noticing.  
 
Quote:
  Don’t get me wrong I do find Dave to be a very interesting DAC/amp and I definitely will hear it then I get an opportunity. The ability to drive a headphone direct from the DAC/amp is a nice future if it can provide the same amplifying capacity of a good standalone amp, including good tuning and driving force etc etc. The “immunity” to the quality of the source gear and digital cables is another attractive aspect.

Yes, you really need to hear it before you judge it and what I say shouldn't matter, your ears will tell you.
 
Mar 14, 2016 at 2:40 PM Post #309 of 1,483

Articnoise

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Okay I got your points and maybe you got what I have tried to say (right or wrong). As I have said I have not heard the Dave yet and therefore cannot say or argument how it sounds like or if the amplifying in Dave is as good as a really good dedicated amp. I’m interested to hear it for myself and will try it as soon as I get a chance. I have one related question, if you don’t mind.

 

Dave is digital-to-analogue convertor with a digital preamplifier. Does it or does it not have an output operational amplifier. If it doesn’t have an amplifier stage on the output. How is the amplifying done exactly? MSB Select II use 16 DACs which together output an audio signal that can be used without an analogue output stage. The Dave isn’t built like that, from what I have understand, so how is the amplifying done?  

 
Mar 15, 2016 at 6:38 AM Post #310 of 1,483

romaz

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  Okay I got your points and maybe you got what I have tried to say (right or wrong). As I have said I have not heard the Dave yet and therefore cannot say or argument how it sounds like or if the amplifying in Dave is as good as a really good dedicated amp. I’m interested to hear it for myself and will try it as soon as I get a chance. I have one related question, if you don’t mind.

 

Dave is digital-to-analogue convertor with a digital preamplifier. Does it or does it not have an output operational amplifier. If it doesn’t have an amplifier stage on the output. How is the amplifying done exactly? MSB Select II use 16 DACs which together output an audio signal that can be used without an analogue output stage. The Dave isn’t built like that, from what I have understand, so how is the amplifying done?  

All your points are very good points and many of them were my points once.  The only difference between us is that this "direct to DAC" experience with a really good DAC is foreign to you right now but once you experience it for yourself through something as good as the DAVE, some of your opinions about this method of listening could change.  I know I am not alone in my opinion about the DAVE.  For a DAC that was just widely released 2 months ago, the DAVE thread here on Head-Fi already has more than 2,100 posts.  This is unprecedented for any DAC, let alone a summit-fi DAC that costs >$10,000.
 
I'm happy to discuss the DAVE further but at the same time, I feel I've been a participant to the derailing of this thread which is supposed to be about music servers so if you wish to discuss DACs further, let's do it through PM or else on the DAVE or some other DAC thread.
 
Mar 15, 2016 at 7:45 AM Post #311 of 1,483

arnaud

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  All your points are very good points and many of them were my points once.  The only difference between us is that this "direct to DAC" experience with a really good DAC is foreign to you right now but once you experience it for yourself through something as good as the DAVE, some of your opinions about this method of listening could change.  I know I am not alone in my opinion about the DAVE.  For a DAC that was just widely released 2 months ago, the DAVE thread here on Head-Fi already has more than 2,100 posts.  This is unprecedented for any DAC, let alone a summit-fi DAC that costs >$10,000.
 
My understanding of DAC technology could be better but this is how I understand it.  As to the DAVE having an op amp, yes, it has several but this requires explanation because it's not what you think.  First of all, all DACs require at least one op amp to do the critical I to V (current to voltage) conversion.  Without some signal generated, then nothing gets sent to the amp.  In fact, most DACs, especially those with both balanced and SE outputs like the DAVE and potentially the Select II (if you order it this way) require several op amps, not just for I to V conversion but also SE to balanced or balanced to SE conversion depending on the starting topology.  With your typical DAC with a built-in headphone amp (Chord excluded), you generally add an output amp to that and so potentially, you have 4 active amps in the analog signal path before the signal reaches your headphone.
 
As I stated before, the more components in your analog path (especially active components like amps), the more transparency suffers and generally, the more distortion is generated and so the high end DAC designers try to minimize the numbers of these components.  Purely SE DACs have the least conversion to perform and can get away with using the least number of op amps which is why purists will often state that SE DACs are more transparent and have less distortion than balanced DACs.  Rob Watts, among others, believes this to be true.  With the Select II, like all DACs, it will require at least one op-amp (to do the I to V conversion) but with the 16 DACs they are using in parallel, this results in such a low impedance that their single op amp is capable of producing enough juice where they don't need to stack a second output amp to create more voltage.  This is how I understand it and this is what they mean by not having an analog output stage but this only holds true if you stay SE with the Select II (at least this is what I believe is true with this DAC).  Once you go balanced, then you have to add at least a second op amp to perform the SE to balanced conversion.  Before you start thinking that a single ended Select II is the only DAC to make this claim, the TotalDac d1-twelve, with its 600 resistors, also has no analog output stage (no output amp).  If anyone ever wondered why the d1-twelve is SE only, this is why.  The problem with the d1-twelve, as I see it, despite its low impedance, the voltage generated by the op-amp of this DAC is so weak that it cannot directly drive a separate outboard amp and so with the d1-twelve, you are forced to use an active preamp to amplify this weak signal which would then drive the amp.  This requires adding another active component to its chain although granted, there are some very good active preamps out there and I have yet to hear of anyone less than happy with their d1-twelve.
 
What about Rob's DACs?  Well, they go one step further.  The simplest DAC+headphone amp in the world that I am aware of is the Chord Mojo because it only consists of 3 components, the FPGA, a discrete DAC and a single op-amp that performs both I to V conversion but also has enough gain to drive headphones.  This simplest of analog stages (a single op amp) is one reason why the Mojo has the same ultra low noise floor as the DAVE (-180dB) and is acclaimed for its transparency.  What about the DAVE?  For convenience sake, Rob included balanced outputs which requires additional op-amps but Rob is quick to tell you that his SE outputs sound better (more transparent and lower distortion).  It is for this same reason that the headphone port on the DAVE is SE only.  If you stay SE  with the DAVE, then like an SE Select II and TotalDac d1-twelve, you are only using a single op-amp.   Unlike the Select II or TotalDac, however, but just like the Mojo, the DAVE's output from its single op-amp can generate enough voltage to drive headphones.  How is it possible that both the DAVE and Mojo can produce this higher voltage off of a single op-amp without generating high distortion?  This is where Rob's ultra high performance analog noise shapers come in and the noise shapers with the DAVE are considerably better than the Mojo.
 
What may be the next Chord revolution is the upcoming amp Rob is now testing for the DAVE.  This amp is unique because I believe it is designed to bypass the op-amp in the DAVE that performs the I to V conversion.  Instead, this new amp (which will initially come in either a 20w or 70w mono block configuration), as I understand it, will perform I to V conversion as well as amplification and so you still have only 1 op-amp in the path but now you aren't just driving headphones, you're driving speakers (or possibly an Abyss or HE-6)!  If this ends up sounding as good and transparent as theory suggests it should, this could be very very big.  
 
I'm happy to discuss the DAVE further but at the same time, I feel I've been a participant to the derailing of this thread which is supposed to be about music servers so if you wish to discuss DACs further, let's do it through PM or else on the DAVE or some other DAC thread.

 
I am no EE major, but you should probably verify the statements you make Romaz about opamps and output stages.
 
As I understand, the very reason why the output stage is removed from the D1 twelve is because it doesn't need one to drive typical preamps (because there are a sufficient number of dacs in parallel to handle the load). Now, a headphone a is much more demanding load than a preamp hence the incapacity to drive such load without an active output stage.
 
Furthermore, there is no opamp in the audio signal path of TotalDAC product as I understand, even for the symmetrisation in case of D1-six (or D1-twelve for that matter). While I can't ascertain myself because I don't have the 2 to compare, the discrete circuit used to convert singled ended output of 6 dacs running in parallel is preferable to using only 4 DAC in differential mode (at least my D1-six sounds more lively, layered and dynamic than my previous dual). By the way, discrete ladder dacs such as that designed by Vincent don't rely on opamps for the I/V by principle...
 
The DAVE sounds interesting (seems like Rob Watt was much needed to help Chord with their designs, I have such dreadful memories of trying some Chord DAC and headphone from a few years ago, before they became all the rage on head-fi!), would definitely like to try it out if your claims are the real deal. But, color me skeptic just a tiny bit for now (like you were before becoming a convert eh :wink: ). 
 
cheers,
arnaud
 
Mar 15, 2016 at 12:05 PM Post #312 of 1,483

romaz

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I am no EE major, but you should probably verify the statements you make Romaz about opamps and output stages.
 
As I understand, the very reason why the output stage is removed from the D1 twelve is because it doesn't need one to drive typical preamps (because there are a sufficient number of dacs in parallel to handle the load). Now, a headphone a is much more demanding load than a preamp hence the incapacity to drive such load without an active output stage.
 
Furthermore, there is no opamp in the audio signal path of TotalDAC product as I understand, even for the symmetrisation in case of D1-six (or D1-twelve for that matter). While I can't ascertain myself because I don't have the 2 to compare, the discrete circuit used to convert singled ended output of 6 dacs running in parallel is preferable to using only 4 DAC in differential mode (at least my D1-six sounds more lively, layered and dynamic than my previous dual). By the way, discrete ladder dacs such as that designed by Vincent don't rely on opamps for the I/V by principle...
 
The DAVE sounds interesting (seems like Rob Watt was much needed to help Chord with their designs, I have such dreadful memories of trying some Chord DAC and headphone from a few years ago, before they became all the rage on head-fi!), would definitely like to try it out if your claims are the real deal. But, color me skeptic just a tiny bit for now (like you were before becoming a convert eh :wink: ). 
 
cheers,
arnaud

Hi Arnaud,
 
Mea culpa!  Thank you for taking me to task on this one, easily my worst post and something I should have done my due diligence on but given the late hour of the night and my earnest intention to answer Articnoise in a timely fashion, I posted what I did, At least I was honest about my statement that my understanding of DAC technology "could be better."  I posted what I was told or at least what I thought I knew.  Everything I said about the DAVE is correct and I have verified this with Rob but with the TotalDac and even the Select, my words were inaccurate and so I apologize for misrepresenting these 2 fine DACs.
 
After an impressive demo of a certain delta-sigma DAC at CES in January, I had a spirited discussion with that DAC's designer who happens to be an electrical engineer.  Not surprisingly, it was his opinion that his DAC was as good as anything out there and so of course, I mentioned a variety of DACs including the Select II, the TotalDacs, the DAVE as well as the Nagra HD, DACs that I not only considered among the best but also DACs that I had some familiarity with   He systematically began to discuss the details of those DACs in comparison to his own, almost as if he had inside information on them and whether I misunderstood him because of our language barrier or whether the technicalities he discussed were just beyond my grasp, I'm not sure but what I mentioned in my post were some of the things I took away from that conversation including his statement that all DACs required at least one op-amp to do the I to V conversion.  Well, it didn't take much searching to realize that neither the TotalDacs nor the MSB DACs, as R2R DACs, rely on op-amps for this reason.  You are correct with your statements on the twelve and Articnoise is correct in his statement that the Select also doesn't rely on op-amps at all.
 
Mar 15, 2016 at 12:42 PM Post #313 of 1,483

paul79

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Right. The Twelve has no output stage at all. No opamps either. The transparency of this DAC is really other worldly, and you can drive amps directly with it, so long as they do not require allot of drive, so most tube amps will be no problem. I get plenty of volume output with my Twelve direct to amps, but I still prefer a world class preamp after it. It is just better, and this has always been the case with any DAC I have had in my system. However, that preamp has to be very damn good.
 
The Twelve gives you the tone of the instrument unlike anything I have heard before in digital. The wood of the instruments, the inflections of voices, backup singers are obvious as day with extreme clarity, etc.... It really sounds like a very high end vinyl setup, and is truly another level in comparison to the Monobloc, or any other Totaldac.
 
I am quite sure the DAVE is on the level, and taken a step further by eliminating the source quality issue. So the potential to save a ton of coin and headache on digital source optimization is very attractive to me. However, my question of "Does the DAVE sound better than the Twelve?", is there, and something I need to hear for myself, because the Twelve is so far ahead of any other DAC I have tried, and has only been bettered by an $80K vinyl rig. This difference was also very slight with regards to extreme resolution and scale, and all else being equal. What really smoked my head was how well the Twelve kept up speed wise with this vinyl rig.
 
Another plus with all the Totaldac's is how well they handle DSD and PCM both. They are indistinguishable and only the recording matters.
 
Mar 15, 2016 at 5:19 PM Post #314 of 1,483

isquirrel

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  All your points are very good points and many of them were my points once.  The only difference between us is that this "direct to DAC" experience with a really good DAC is foreign to you right now but once you experience it for yourself through something as good as the DAVE, some of your opinions about this method of listening could change.  I know I am not alone in my opinion about the DAVE.  For a DAC that was just widely released 2 months ago, the DAVE thread here on Head-Fi already has more than 2,100 posts.  This is unprecedented for any DAC, let alone a summit-fi DAC that costs >$10,000.
 
My understanding of DAC technology could be better but this is how I understand it.  As to the DAVE having an op amp, yes, it has several but this requires explanation because it's not what you think.  First of all, all DACs require at least one op amp to do the critical I to V (current to voltage) conversion.  Without some signal generated, then nothing gets sent to the amp.  In fact, most DACs, especially those with both balanced and SE outputs like the DAVE and potentially the Select II (if you order it this way) require several op amps, not just for I to V conversion but also SE to balanced or balanced to SE conversion depending on the starting topology.  With your typical DAC with a built-in headphone amp (Chord excluded), you generally add an output amp to that and so potentially, you have 4 active amps in the analog signal path before the signal reaches your headphone.
 
As I stated before, the more components in your analog path (especially active components like amps), the more transparency suffers and generally, the more distortion is generated and so the high end DAC designers try to minimize the numbers of these components.  Purely SE DACs have the least conversion to perform and can get away with using the least number of op amps which is why purists will often state that SE DACs are more transparent and have less distortion than balanced DACs.  Rob Watts, among others, believes this to be true.  With the Select II, like all DACs, it will require at least one op-amp (to do the I to V conversion) but with the 16 DACs they are using in parallel, this results in such a low impedance that their single op amp is capable of producing enough juice where they don't need to stack a second output amp to create more voltage.  This is how I understand it and this is what they mean by not having an analog output stage but this only holds true if you stay SE with the Select II (at least this is what I believe is true with this DAC).  Once you go balanced, then you have to add at least a second op amp to perform the SE to balanced conversion.  Before you start thinking that a single ended Select II is the only DAC to make this claim, the TotalDac d1-twelve, with its 600 resistors, also has no analog output stage (no output amp).  If anyone ever wondered why the d1-twelve is SE only, this is why.  The problem with the d1-twelve, as I see it, despite its low impedance, the voltage generated by the op-amp of this DAC is so weak that it cannot directly drive a separate outboard amp and so with the d1-twelve, you are forced to use an active preamp to amplify this weak signal which would then drive the amp.  This requires adding another active component to its chain although granted, there are some very good active preamps out there and I have yet to hear of anyone less than happy with their d1-twelve.
 
What about Rob's DACs?  Well, they go one step further.  The simplest DAC+headphone amp in the world that I am aware of is the Chord Mojo because it only consists of 3 components, the FPGA, a discrete DAC and a single op-amp that performs both I to V conversion but also has enough gain to drive headphones.  This simplest of analog stages (a single op amp) is one reason why the Mojo has the same ultra low noise floor as the DAVE (-180dB) and is acclaimed for its transparency.  What about the DAVE?  For convenience sake, Rob included balanced outputs which requires additional op-amps but Rob is quick to tell you that his SE outputs sound better (more transparent and lower distortion).  It is for this same reason that the headphone port on the DAVE is SE only.  If you stay SE  with the DAVE, then like an SE Select II and TotalDac d1-twelve, you are only using a single op-amp.   Unlike the Select II or TotalDac, however, but just like the Mojo, the DAVE's output from its single op-amp can generate enough voltage to drive headphones.  How is it possible that both the DAVE and Mojo can produce this higher voltage off of a single op-amp without generating high distortion?  This is where Rob's ultra high performance analog noise shapers come in and the noise shapers with the DAVE are considerably better than the Mojo.
 
What may be the next Chord revolution is the upcoming amp Rob is now testing for the DAVE.  This amp is unique because I believe it is designed to bypass the op-amp in the DAVE that performs the I to V conversion.  Instead, this new amp (which will initially come in either a 20w or 70w mono block configuration), as I understand it, will perform I to V conversion as well as amplification and so you still have only 1 op-amp in the path but now you aren't just driving headphones, you're driving speakers (or possibly an Abyss or HE-6)!  If this ends up sounding as good and transparent as theory suggests it should, this could be very very big.  
 
I'm happy to discuss the DAVE further but at the same time, I feel I've been a participant to the derailing of this thread which is supposed to be about music servers so if you wish to discuss DACs further, let's do it through PM or else on the DAVE or some other DAC thread.


Sorry Roy, have to interrupt here, respectfully my friend. The information you are giving out about the MSB Select II is incorrect. I suggest anyone looking for a correct explanation of how the Select works and you have to understand there are a great many technologies inside it that MSB will never make public even to its distributors and dealers. I suggest you contact Jonathan Gullman at jonathan@msbtech.com for further clarification on the facts not speculation.
 
Mar 15, 2016 at 5:23 PM Post #315 of 1,483

romaz

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Sorry Roy, have to interrupt here, respectfully my friend. The information you are giving out about the MSB Select II is incorrect. I suggest anyone looking for a correct explanation of how the Select works and you have to understand there are a great many technologies inside it that MSB will never make public even to its distributors and dealers. I suggest you contact Jonathan Gullman at jonathan@msbtech.com for further clarification on the facts not speculation.

Hi Simon, yes, I already owned up to my mistake and apologized.  I was fed misinformation and went with it.  Once again, mea culpa, and as I stated, I have no plans for further DAC discussions here.  So no one else stumbles upon that post and decides to take it as gospel truth, I have edited it out.
 

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