[ChicaneBT]

Quote:

1. I've already posted RMAA and several other types of measurements for the DAC I use on head-fi. I will not post them here because I do not wish to clutter the thread. The measurements are higher across the board. Granted it is a $500 DAC, however it includes 12 balanced ins and 12 balanced outs.
2. He has omitted basic, but essential/important detail. I have already described why in previous posts in this thread. For the sake of clarity, I will not repost them a third time.
3. I do not have to prove anything for his measurements. I do not wish to say that they are wrong, nor have I ever implied that. Please use your head and understanding of language to understand the simple premise I have repeated consistently: nwavguy has not posted information that are essential to truly understanding the REAL WORLD performance of an amplifier. Some of which (eg. reactive load for all headphones) are unreasonable to expect. Others which are not (eg. 16 bit performance, example reactive load performance, what load type he was using).
4. 16 bit performance will show how the dac performs taking 16 bit performance (without padding etc), outputting a 16 bit conversion. Which I presume (having not looked specifically at the devices architecture in detail), many are doing.
5. I am not arguing against the product produced. I am arguing against the method in which it has been produced (potential plagiarism of the coffee, and so on).

Where can I (and others) find your measurements of the Focusrite?
 
Maybe someone will post some 16 bit performance measurements .

 

[MrGreen]

Quote:

Where can I (and others) find your measurements of the Focusrite?
 
Maybe someone will post some 16 bit performance measurements .

I use echo hardware.



For the purpose of maintaining clutter, I'll only post RMAA as one picture and not other measurements (jitter etc, since my hardware supports things like external clocks). I've measured similar results -almost identical in fact- in the pass (with worse channel separation due to an error on my part).







I hope someone decides to be a smart arse and tells me I am not posting enough information. It would make my day.

PS an alternative source quotes "Rightmark's Audio Analyser roughly confirmed the manufacturer's specification, with a very good and almost identical measured 24-bit dynamic range of 110dBA at 44.1kHz, 96kHz and 192kHz sample rates, and a flat frequency response with -0.5dB points at 6Hz to 21.5kHz with a 44.1kHz sample rate, extending at the top end to 44kHz with a 96kHz sample rate, and staying about the same at 192kHz. Total harmonic distortion measured an extremely low 0.0004 percent, while stereo crosstalk was also excellent at -111dB"

FWIW I wouldn't take my measurements as gospel on the hardware I use. It may be different in your setup. Some of it appears off to me; for example the DNR is lower than the SNR in the 24bit measurement. To my understanding that is a questionable reading; the SNR should be of a random or average signal value, and the dynamic range shoudl be the loudest possible signal.

One thing I'd like someone to shed light on is the different things used by nwavguy here for the odac, fiio and dac1
 
Noise A-Weighted dBu 24/44 --102.8 dBu A -98.3 dBu C -105.4 dBu
Dynamic Range –60 dBFS A-Wtd --111.1 dBr A -97.6 dBr C -110.9 dBr

Is he trying to tell me that he is using A weighting for his gear, C weighting for the fiio, and unweighted results for the DAC1? Am I reading it wrong? Or is it an error?

 

[Anaxilus]

Quote:

So I stand by the character assassination term (which was partly aimed at Anaxilus).

 
If you think asking someone to adhere to the same standards they apply to others who are actually having their character assassinated is assassination then so be it.  I have no problem w/ you or anyone using the term incorrectly.  Maybe sacrilegious is the term you were looking for.  These questions have been asked multiple times for more than a year w/o response.  I'm sure he's worried about being held legally accountable for many of his claims and statements which is why he hides behind his 'incomplete profile'.

 

[ChicaneBT]

Quote:

I use echo hardware.



For the purpose of maintaining clutter, I'll only post RMAA as one picture and not other measurements (jitter etc, since my hardware supports things like external clocks). I've measured similar results -almost identical in fact- in the pass (with worse channel separation due to an error on my part).







I hope someone decides to be a smart arse and tells me I am not posting enough information. It would make my day.

PS an alternative source quotes "Rightmark's Audio Analyser roughly confirmed the manufacturer's specification, with a very good and almost identical measured 24-bit dynamic range of 110dBA at 44.1kHz, 96kHz and 192kHz sample rates, and a flat frequency response with -0.5dB points at 6Hz to 21.5kHz with a 44.1kHz sample rate, extending at the top end to 44kHz with a 96kHz sample rate, and staying about the same at 192kHz. Total harmonic distortion measured an extremely low 0.0004 percent, while stereo crosstalk was also excellent at -111dB"

FWIW I wouldn't take my measurements as gospel on the hardware I use. It may be different in your setup. Some of it appears off to me; for example the DNR is lower than the SNR in the 24bit measurement. To my understanding that is a questionable reading; the SNR should be of a random or average signal value, and the dynamic range shoudl be the loudest possible signal.

One thing I'd like someone to shed light on is the different things used by nwavguy here for the odac, fiio and dac1
 
Noise A-Weighted dBu 24/44 --102.8 dBu A -98.3 dBu C -105.4 dBu
Dynamic Range –60 dBFS A-Wtd --111.1 dBr A -97.6 dBr C -110.9 dBr

Is he trying to tell me that he is using A weighting for his gear, C weighting for the fiio, and unweighted results for the DAC1? Am I reading it wrong? Or is it an error?

The DAC1 Pre has no grade because it's considered as the benchmark for the ODAC or any DAC he has reviewed. The Fiio and ODAC have grades how they compare to the DAC1 Pre. Grade A being best, grade F being worst, that are the letters behind the measurements. He probably has written some stuff about why a result of a measurement is good and when it's not good enough for an A grade. 
 
Too bad I can't view your picture.
 
Edit:
Noise A-Weighted dBu 24/44 is the measurement --102.8 dBu is the result A is the grade -98.3 dBu is the result C is the grade -105.4 dBu is the result and the benchmark
 
This is probably makes it clearer . The grade A or C has nothing to do with the A-Weighting which is a part of the measurement.

 

[Parall3l]

Quote:

The DAC1 Pre has no grade because it's considered as the benchmark for the ODAC or any DAC he has reviewed. The Fiio and ODAC have grades how they compare to the DAC1 Pre. Grade A being best, grade F being worst, that are the letters behind the measurements. He probably has written some stuff about why a result of a measurement is good and when it's not good enough for an A grade. 
 
Too bad I can't view your picture.

If I read that right

http://en.wikipedia.org/wiki/A-weighting

 

[ChicaneBT]

Noise A-Weighted dBu 24/44 is the measurement --102.8 dBu is the result A is the grade -98.3 dBu is the result C is the grade -105.4 dBu is the result and the benchmark
 
This is probably makes it clearer .

 

[MrGreen]

Oh, okay. He threw me off for a second there.

My picture was removed (possibly by mods?). You can probably find it on my profile.

 

[mikeaj]

some responses in bold
 
Quote:

1. I've already posted RMAA and several other types of measurements for the DAC I use on head-fi. I will not post them here because I do not wish to clutter the thread. The measurements are higher across the board. Granted it is a $500 DAC, however it includes 12 balanced ins and 12 balanced outs.
 
As you've mentioned earlier, a lot of RMAA figures don't seem to add up—SNR and dynamic range not making sense together; others have noticed seemingly impossible crosstalk readings, other issues.  Those who have done their own recording trying to match RMAA's setup, doing their own math, seem to have come up with a different figures than RMAA does.  And as we all know, there are instrumentation challenges, mostly dealing with grounding, not to mention having to deal with ADC quality.
 
I guess the important thing for everybody to keep in mind are that RMAA results have no absolute reference and peoples' setups are way different, so results from different sources are not at all comparable.
 
I also really think that at $150, ODAC is probably not such a good value.  My guess is that many sound cards and other interfaces can offer similar performance or better; the benefit of an ODAC or something else over those is just being external and USB, using UAC1 drivers.  It's just most of the audiophile stereo DACs that are way overpriced, as far as I can tell.
 
 
2. He has omitted basic, but essential/important detail. I have already described why in previous posts in this thread. For the sake of clarity, I will not repost them a third time.
 
I agree on important details being missing.  Some people are not really getting the right perspective.
 
 
3. I do not have to prove anything for his measurements. I do not wish to say that they are wrong, nor have I ever implied that. Please use your head and understanding of language to understand the simple premise I have repeated consistently: nwavguy has not posted information that are essential to truly understanding the REAL WORLD performance of an amplifier. Some of which (eg. reactive load for all headphones) are unreasonable to expect. Others which are not (eg. 16 bit performance, example reactive load performance, what load type he was using).
 
The standard argument here seems to be that most amps are pretty much voltage sources and if output impedance is low enough, there should be small effects from driving real-world reactive loads as opposed to dummy resistors.  That said, I'd always bug people to use real-world loads, just to see if they can show differences.  Maybe when Tyll gets his amp testing setup up and running, we can all ask him to look at it.  With my own very informal, very inaccurate, RMAA-based testing, at a given voltage output I have seen amps struggle with an 80 ohm nominal headphone (has a midbass hump) more than a 32 ohm nominal headphone (fairly resistive).  With just resistors, you would expect distortion to be lower for the 80 ohm load.
 
On a related note, you can see the effect of a higher-Z output in this Benchmark Media white paper (for what that's worth):
http://www.benchmarkmedia.com/discuss/feedback/newsletter/2011/12/2/0-ohm-headphone-amplifier-sonic-advantages-low-impedance-headphone-amp
 
Of course they're just taking electrical measurements, not acoustic.  Acoustic measurements would probably mask most differences they're trying to show, not to mention being much more of a pain to set up.
 
 
4. 16 bit performance will show how the dac performs taking 16 bit performance (without padding etc), outputting a 16 bit conversion. Which I presume (having not looked specifically at the devices architecture in detail), many are doing.
 
I don't see a reason why you wouldn't just set 24-bit mode.  However, many people probably use plenty of 24-bit and 32-bit devices in 16-bit mode, and I agree that 16-bit performance is worth investigating.  As you say, it seems like he may just be busy—more performance figures for the ODAC are promised, but they've yet to materialize.
 

5. I am not arguing against the product produced. I am arguing against the method in which it has been produced (potential plagiarism of the coffee, and so on).
 
Whether or not anybody believes it, I think the claim made would be that he was unaware of the Calyx Coffee.  Regardless, is it really such plagiarism to use the same DAC and USB receiver chip as another device?  Most of the design effort and performance comes from the board layout, optimizing other parts, etc.  Certain parts are common and make sense to use, in audio and otherwise, so can you really blame multiple people from using them?  I hope nobody thinks either the O2 or ODAC are complete breakthroughs in terms of circuit design.

 

[rhythmdevils]

Quote:

 
If you think asking someone to adhere to the same standards they apply to others who are actually having their character assassinated is assassination then so be it.  I have no problem w/ you or anyone using the term incorrectly.  Maybe sacrilegious is the term you were looking for.  These questions have been asked multiple times for more than a year w/o response.  I'm sure he's worried about being held legally accountable for many of his claims and statements which is why he hides behind his 'incomplete profile'.

 
Agreed, and well put.  If you think the points being made here amount to character assassination, I'd be horrified to know what the word is for the methods NwavGuy used to attack good, honest people like Schitt and AMB.  I have nothing against pointing out problems using measurements, I'm all for it.  But Nwavguy didn't just point out problems, his goal wasn't bettter products or more awareness, his goal was to shame them, embarrass them, humiliate them, and ruin their reputation. 

 

[mikeaj]

Quote:

Agreed, and well put.  If you think the points being made here amount to character assassination, I'd be horrified to know what the word is for the methods NwavGuy used to attack good, honest people like Schitt and AMB.  I have nothing against pointing out problems using measurements, I'm all for it.  But Nwavguy didn't just point out problems, his goal wasn't bettter products or more awareness, his goal was to shame them, embarrass them, humiliate them, and ruin their reputation. 

 
kinda OT so response in spoiler
 
 

Spoiler: Warning%3A%20Spoiler!

I'm sure different people have different impressions on methods used (certainly I wouldn't take the exact same approach), but aren't doing things like shaming / embarrassing / humiliating part of promoting better products, by bringing down worse products?  Again, you can disagree with how "worse" is defined, as usual.  Anyway, what's the use of mincing words:  protecting peoples' feelings?  Why should we care about the designers' intentions, if they mean well, or if we think they're good people?
 
 
Also, I see a big difference between exposing objective issues that others can and have verified, and insinuation about ulterior motives that don't seem like they can be substantiated at all.  Wake me up when somebody's actually dug up some dirt.  I encourage some skepticism too, but again:  one thing is skepticism; on the other hand, we have true and verifiable issues.  That said, some from every side are guilty of some speculation, based on various degrees of evidence.
 
The thing I wonder about insinuations of kickbacks involved, is about who would be sending the money:  John from JDSLabs, Oliver from Epiphany Acoustics?  Really?  Normally I'd just dismiss this as a strawman argument for the extreme, but it's been brought up more than once.
 
 
If anybody can expose poor design, bad measurements, or anything, I don't much care how they say it.  Or who the target is.  Actually, if you could expose new issues with the O2 or ODAC, that would be perfect.

 
 
So have people been having driver issues with the ODAC lately?  More USB cables making a difference?  Ferrite beads?  How, in which situation, and by how much?

 

[MrGreen]

Quote:

 

Good post. Only one aspect I wish to respond to. "Regardless, is it really such plagiarism to use the same DAC and USB receiver chip as another device? "

As some what of a free information activist, I would not consider this plagiarism. I would go further to say that the concept of plagiarism has become obtrusive. How is reading the work of another an invalid form of research? How is taking, and improving the work of another or changing it to your benefit, an invalid form of research? In essence, I would say that plagiarism has become a term that reinforces the plutocracy. It belittles those studying, researching, and modifying known technology for their own benefit. It stifles progress. We see it time and time again in the United States with patent laws. Classic examples would be Apple coming out with numerous lawsuits based on patents filed on unrealised, otherwise unpublished technology. I do not personally approve of the term, however I do not approve of stealing information at the DIRECT expense of another. For example, Steve Jobs stealing from Woz. The other side of the coin, is when your new product obsoletes the former product. I do agree with this form of "shifting power", because it encourages progress (in ways that capitalism now often fails to do).

As per above, I have no doubt that many would consider it plagiarism - including the american judicial system.
 
((You'll have to excuse me, I've been watching many very convincing tin-foil hat tier documentaries))
 
 
 
Quote:

*Responding to spoilers*

Frankly I'm more concerned by how impressed/mesmerised people are over readily available, and very public information than I am about the feelings of people who create rival products. To me, it speaks volumes about the community - moreso than nwavguys own actions. Not that I specifically condone his actions.

One thing I remember about schiit audio was the marketing spin they put on specifications (something I loathe totally). Something about the "amazing output levels" (needlessly high??) of the schiit asgard. In essence, nwavguys philosophy is the same as "all the fat cats in washington are liars", and then his measurements become another form of marketing. By adding marketing to the equation, I think the purpose of measurements are corrupted. We have seen it in the display industry (contrast ratio, dynamic contrast ratio, color spaces other than LAB and LUV), and even the pharmaceutical industry. (I'm a wide-read conspiracy nut). That is not to say that I don't approve of "marketing" a measurably superior product. But when the marketing becomes the focus - I think we're in for some trouble. Rediculous gains on nearly every headphone amp in existence comes to mind (remind me again why it's acceptable to only have to turn your volume knob 10% of the way?) EDIT:: Except for maybe I think AB design which means the less I push it, the better the THD? Maybe I am wrong.


Perhaps I should take my ideas to arch forums, but I preferred the DIY community when it was about sharing designs and concepts, without the need of potentially profit-motivated agenda.

Regardless, I'll be the first to point out that amps and dacs aren't really my element, as I prefer to stick with headphone measurements. I understand the measurements, but I couldn't sit there and tell you how to improve an amplifier. So anyone can correct me at any stage.

 

[gnarlsagan]

kinda OT so response in spoiler

Spoiler: Warning: Spoiler!

I'm sure different people have different impressions on methods used (certainly I wouldn't take the exact same approach), but aren't doing things like shaming / embarrassing / humiliating part of promoting better products, by bringing down worse products?  Again, you can disagree with how "worse" is defined, as usual.  Anyway, what's the use of mincing words:  protecting peoples' feelings?  Why should we care about the designers' intentions, if they mean well, or if we think they're good people?


Also, I see a big difference between exposing objective issues that others can and have verified, and insinuation about ulterior motives that don't seem like they can be substantiated at all.  Wake me up when somebody's actually dug up some dirt.  I encourage some skepticism too, but again:  one thing is skepticism; on the other hand, we have true and verifiable issues.  That said, some from every side are guilty of some speculation, based on various degrees of evidence.

The thing I wonder about insinuations of kickbacks involved, is about who would be sending the money:  John from JDSLabs, Oliver from Epiphany Acoustics?  Really?  Normally I'd just dismiss this as a strawman argument for the extreme, but it's been brought up more than once.


If anybody can expose poor design, bad measurements, or anything, I don't much care how they say it.  Or who the target is.  Actually, if you could expose new issues with the O2 or ODAC, that would be perfect.

So have people been having driver issues with the ODAC lately?  More USB cables making a difference?  Ferrite beads?  How, in which situation, and by how much?

+1

It's one thing to call someone's reputation into question over evidence (destroyed headphones, unsubstantiated claims, lack of responsibility) and quite another to accuse someone based on no evidence at all. I'm not a business man, but I don't see an income stream here. If there is reason to think otherwise I would flip flop instantly, but I just don't see it. When certain companies release a lot more specific info about their products it will be easier to refrain from pointing out flaws in those products and those who market said products. And no one's saying anything about companies who are more transparent with their designs and results.

I'm not tied to one side here but this seems to be the most reasonable way to look at it.

MrGreen I'd like to ask the questions you've proposed, since they have some obvious merit. Perhaps let's wait for the next article and see if they are addressed, and if not maybe we can get some answers. It'd be nice if anyone knew someone else who could run the measurements, because those answers would be more definitive to those who doubt nwavguy's motivations. I'm certaintly interested in more info about this and other amps as well. A scientific approach to all this seems to be rather new in the scope of things.

 

[estreeter]

I will only say this - in their headlong rush to find a cheaper alternative to the expensive kit offered by most vendors. many have embraced the whole 'V package' without questioning whether it was just another flavor of Kool-Aid. Surely there is room in the audio universe for more than one colossal ego, regardless of how well his designs measure ? Just sayin'. 

 

[Anaxilus]

Well then, when one has nothing to hide they should probably answer the damned questions, offer evidence and stop hiding.  I'm amazed at the number of libelous claims made that his supporters overlook or are somehow blind too.  I don't know if it's selective reading, memory or both.
 
If you don't see a potential revenue stream I'd recommend avoiding a job at the Dept of Treasury or FBI.

 

[mikeaj]

Quote:

Well then, when one has nothing to hide they should probably answer the damned questions, offer evidence and stop hiding.  I'm amazed at the number of libelous claims made that his supporters overlook or are somehow blind too.  I don't know if it's selective reading, memory or both.
 
If you don't see a potential revenue stream I'd recommend avoiding a job at the Dept of Treasury or FBI.

 
Uh, I really don't read that much into anything that's not the graphs, engineering analysis, or factual descriptions of what others have done, because much of it is frankly not that interesting and tends to be less accurate anyhow.  So I'm probably forgetting things.  I guess that counts as selective reading?  
 
So which parties do you think were subjected to libelous claims?  C-Media, FiiO, Asus, Creative, Chinese audio companies as a whole, NuForce, AMB, Schiit, Head-Fi / Jude (and a couple others)?  I don't remember anything else off the top of my head.  I think in the majority of the above, criticisms are legitimate and well founded, based on actual products and tests.  For some cases, mostly involving interpreting others' motivations, there are probably some errors and definitely some conclusions I wouldn't be comfortable leaping to myself.
 
All in all, I think you'll find plenty worse across the Internet, most just not as widely read or believed if we're just talking about audio.  On a side note, how would you rate this in relation to Arthur Salvatore on Stereophile?
 
 
Also, there seems to be an inordinate amount of effort spent on shooting down the messenger rather than dealing with the messages, like proving them wrong.  Shouldn't that be the easiest way to stop the zombie invasion?  There are some open challenges that should be easy to win...?
 
 
I have no interest in positions at the Department of the Treasury or the FBI, so would you mind suggesting some of the potential revenue streams?  (I mean to say:  I can think of plenty, but not many that are above the level of the average conspiracy theory.)