[gevorg]

Nwavguy, do what you think is right and don't let NuForce intimidate you with their personal attacks. As stated previously, all NuForce is doing now is damage control, and their so called "rebuttal" spends more time questioning your competence and discussing subjective matters. NuForce lost my respect the moment they started quietly changing specs on their uDAC page. Personally, I would like to see your analysis on other gear popular on HeadFi. uDAC is not worth all this time anymore, the cat is already out of the bag. 

 
 

 

[blockhead]

[size=10pt]For the TLDR type of member, this seems to be the most relevant paragraph regarding the 0 dBFS clipping. [/size]
 
[size=10pt]"If we had done as the reviewer suggests and prevented the DAC from slightly clipping the signal and then had compensated by increasing the gain after the DAC stage in the analog domain, a sacrifice of the Signal to Noise Ratio (SNR) would have resulted.  As stated earlier, our experience is that the average user is far more sensitive to residual noise levels than they are to a slight loss of dynamic resolution, which in all but the most extreme "audio purist" cases would never be noticed.  Therefore, our goal with the uDac-2 was to (basically) squeeze every last dB of SNR out of it without adversely affecting other parameters in any significant way."  [/size]
 
There seems to be a large part of the response devoted to the fact that 0.67% distortion is inaudible (and I'm not in a position to argue). What were the gains in SNR because of this ? When you refer to residual noise levels do you mean hiss/SNR (due to needing higher gain in the analog domain)? If so was it a trade-off between hiss and (seemingly inaudible) distortion?
 
Sorry if this was already clear but the second sentence I quoted seems to refer to a trade-off between "residual noise" and "dynamic resolution" and unless I'm wrong again this would only happen if the user reduced the digital levels to eliminate the distortion?
 
[size=10pt]@nwavguy. I'll choose option 2 thanks![/size]
 
@SLCanhead. I disagree nobody had crossed the line in this thread. In fact kudos to NuForce and Nwavguy IMHO.
 
I have to agree with the member above (though less strongly) that having incorrect measument data on the product page is a bad look.

 

[faileas]

Gevorg: What *would* an appropriate response to a claim that a device is flawed, based on technical information be, if nuforce believed that the device in question worked within parameters? I also think a heavy part of sound is subjective - the very same example that the original poster gave of nuforce being 'wrong' had two interesting things about it - the reviewer felt it sounded great, and where there was room for improvement, nuforce did it. Quite a few reviewers tend to give the udac2 good reviews - headphonia, for example .
 
Nwavguy: Small thing i noticed with subjective tests is, you only used IEMs to test. I'm noticing a slight pattern with many of the positive (subjective) reviews that they are using full sized headphones. You might, if its possible, try to repeat that part with something full sized. I'd also note that a significant number of your possible test DACS wouldn't even work acceptably with your preferred headphones, by your own admission, so it would allow you to run fairer subjective/listening tests, on your own side.
 
EDIT: added the thing i wanted to ask nwaveguy... headfi occationally decides i should not be allowed to use the return key ><
 
 
 
 
 
 
 

 

 

[jasonl]

 
I have to agree with the member above (though less strongly) that having incorrect measument data on the product page is a bad look.

Agree, we are not perfect. The SNR was changed to be more conservative. Every company made mistakes on products, spec, manual etc. No matter how much resources you have, something is bound to slip through.  If it is a mistake, we readily admit. So when NWAVGuy first contacted us without any further explanation about how and when he purchased the uDAC-2. Out of our sincere concern that he could have one of the 1st production uDAC-2 with noise problem (even though we believe that customers were all contacted and fixed but perhaps it came from a dealer), so that's the first thing I ask. If we are trying to hide any problem, we would have hide being the usual PR bs and ask him to send in the UDAC-2.  It is our customer service policy to take care of problem (most of the time we send replacement first with return shipping label) no matter what.
 
The whole issue started when NWAVGuy insisted that we have to admit that having 0.67% THD+N is a mistake. I responded that we disagreed and then it got into this whole argument and personal attack about the company.

 

[jasonl]

Well, if there is something positive about this whole episode is the debate about which measurements matters and how we perceive sound. Some people lough at high-end audio hobby. Before I co-founded Nuforce, I was skeptical too.
How we perceive sound is very complex. Sure, may be everything can be measured. But I think we are far from that.
Over the years, I began to learn to to differentiate various audiophile concept.  Can you really hear the sonic characteristic of a 300 year old cello played by a top musician through a sound system? Yes, and I will never forget the hair standing and almost tearful experience when I heard the same track (we brought along the CD) at a top recording engineer's listening lab in LA, CA.
Measurement only take us so far. Therefore listening and tuning is something that we spent a lot of time too.
For those of you interested in demo tracks that illustrate various audiophile concept, you can download them from
http://www.nuforce.com/hp/media/Nuforce%20Demo1/index.php
Most of the tracks are less than 60 seconds.
 
Quote:

Gevorg: What *would* an appropriate response to a claim that a device is flawed, based on technical information be, if nuforce believed that the device in question worked within parameters? I also think a heavy part of sound is subjective - the very same example that the original poster gave of nuforce being 'wrong' had two interesting things about it - the reviewer felt it sounded great, and where there was room for improvement, nuforce did it. Quite a few reviewers tend to give the udac2 good reviews - headphonia, for example .
 
Nwavguy: Small thing i noticed with subjective tests is, you only used IEMs to test. I'm noticing a slight pattern with many of the positive (subjective) reviews that they are using full sized headphones. You might, if its possible, try to repeat that part with something full sized. I'd also note that a significant number of your possible test DACS wouldn't even work acceptably with your preferred headphones, by your own admission, so it would allow you to run fairer subjective/listening tests, on your own side.
 
EDIT: added the thing i wanted to ask nwaveguy... headfi occationally decides i should not be allowed to use the return key ><
 
 
 
 
 
 
 

 

 

 

[SLCanhead]

 
Quote:

[size=10pt]For the TLDR type of member, this seems to be the most relevant paragraph regarding the 0 dBFS clipping. [/size]
 
[size=10pt]"If we had done as the reviewer suggests and prevented the DAC from slightly clipping the signal and then had compensated by increasing the gain after the DAC stage in the analog domain, a sacrifice of the Signal to Noise Ratio (SNR) would have resulted.  As stated earlier, our experience is that the average user is far more sensitive to residual noise levels than they are to a slight loss of dynamic resolution, which in all but the most extreme "audio purist" cases would never be noticed.  Therefore, our goal with the uDac-2 was to (basically) squeeze every last dB of SNR out of it without adversely affecting other parameters in any significant way."  [/size]
 
There seems to be a large part of the response devoted to the fact that 0.67% distortion is inaudible (and I'm not in a position to argue). What were the gains in SNR because of this ? When you refer to residual noise levels do you mean hiss/SNR (due to needing higher gain in the analog domain)? If so was it a trade-off between hiss and (seemingly inaudible) distortion?
 
Sorry if this was already clear but the second sentence I quoted seems to refer to a trade-off between "residual noise" and "dynamic resolution" and unless I'm wrong again this would only happen if the user reduced the digital levels to eliminate the distortion?
 
[size=10pt]@nwavguy. I'll choose option 2 thanks![/size]
 
@SLCanhead. I disagree nobody had crossed the line in this thread. In fact kudos to NuForce and Nwavguy IMHO.
 
I have to agree with the member above (though less strongly) that having incorrect measument data on the product page is a bad look.

We are all entitled to our opinion. However, even in a forum environment, this is just getting silly. What is being accomplished that hasn't already been pointed out/discussed (as I believe someone previously mentioned in one of these threads)?
 
Well, I guess maybe you are right. Maybe, I am just not seeing this right. This could just be healthy debate. So march on! Fight the good fight!
 

 

[HeadphoneAddict]

Quote:

I would please like some input from others who have been following this thread. I can approach the lengthy NuForce response several different ways. I could:
 

• Just let it end here. I've tried to make my concerns about the product, and NuForce's earlier response and position known already.
• Respond to a few of what I consider the more potentially misleading points in their long response.
• Respond with a similar level of detail to what they've provided.

 
...
 
So what should I do here? Let it drop? Challenge NuForce on some of the bigger points? Or provide a detailed response? I don't want to spend hours writing a detailed response if nobody cares or will even bother to read it. This thread has already gone on far longer than I had planned.
 
Also, some other obligations may prevent my immediate response (especially if it's the lengthy one). But don't take that as a lack of interest in my part. I honestly would like to do what fellow head-fier's think is best here?
 

Well, I would just let it drop at this point.  I think you've accomplished what you set out to do.  I just hate to see arguments of this kind that continue unabated, when both sides can't be swayed, as it just drags everyone down with it.
 

 

[jasonl]

Yes, this is silly. If NWAVGuy happens to be in the bay area, I will buy you a nice dinner and invite you to our listening room for a healthy discussion about audiophiles pursuit of sound quality.
And you can compare CDP-8 before and after the change. You can also compare against OPPO BDP-93 and BDP-93NE.  This hobby is addictive once you open your ears to it.
 
Oh, by the way, with regards to BDP-93NE and BDP-93, you can check out Secrets of Home Theater review of both units. That generated another debate but we kept it civilize with no accusations. It is very interesting to compare the plot of both machines and hear the sound characteristic. Why do people pay much more to eat fine food? Same reasoning here.
For $400 of upgrade (not modification but a different design), it is the price of a few dinner for two.  But we get to enjoy a sound characteristic that we love for many years (or until such player is replaced). This is life's pleasure.

 

[xnor]

subscribed, in case nwavguy will reply ^_^ (I wouldn't mind a lengthy, informative post)

 

[nick_charles]

So from the Stereophile review on the first sample of the Nuforce CD player sample we might infer evidence to support either
 
(a) that a CD player with very high jitter ( 3 plus ns) and other poor noise and distortion measurements can actually sound subjectively good or
(b) that Stereophiles listener is stone deaf ?
 
This is far from the first time that John Atkinson has been bemused and pondered why his subjective reviewers liked a product that was actually pretty low fi.
 
If a then jitter does not look like a real issue after all ?
 
If b then perhaps their recomendations ought to be taken with a pinch of salt
 
As Stereophile has this neurotic tension between being a predominantly highly subjectivist magazine but are also obsessed over the degrading effects of jitter, how do they square this ?
 
Fascinating...
 
 
 

 

[kostalex]

^ Fascinating post. Touché!

 

[SP Wild]

Its actually not a difficult thing to stick two probes on two electrical contacts to take measurements, then learn how to use the software to show these measurements, or even learning how interpret these measurements...not hard at all. 
 
It is difficult to engineer, design and implement a circuit.
 
I don't think this observation of mine can be challenged.  Or the fact that personal preferences will remain as such.
 
My 2 cents.
 
 

 

[bulmanxxi]

I have tried to like NuForce Icon Mobile and uDac and uDac-2.  I've had literally had seven of them simply because they are so affordable BUT they ALL had issues.  The uDac was just poor sounding - worse than a macbook pro output.  Icon Mobile has had either terrible noise with USB input OR terrible random popping sounds via analog input.  uDac-2 main issue for me has been the channel imbalance - simply unacceptable.  I listen mostly at low volume and my right channel is virtually missing - $129 to listen to MONO?!  Seriously?!  Otherwise, it sounded good but not necessarily better than my MacBook Pro output.  But I've sold or return all of their products and do not intend to purchase more.  My experiences have little to do with the measurements discussed here - but the bottom line is that overall HYPE on this forum (way past NuForce products) is beyond belief...  Seriously!!!  It is evident most people can't tell the difference between DACs!  It is probably just as clear those same people can't hear the difference between their own PCs/MACs and an added DAC.  Therefore, the only WINNERS here are the manufacturers (and perhaps the forum itself through the advertisements and whatever else they get from manufactures here) selling snake oil stuff.  Even when there has been a slight improvement in SQ with some equipment HYPED up here, the COST and/or the INCONVENIENCE of using such products has been truly ridiculous!!!

 

[SP Wild]

Seven of them, wow.  I'd like to think I would have learned my lesson by the second time.

 

[bulmanxxi]

Furthermore, seems like this industry may need some regulation (or self regulation) or an independent body testing and validating claims to protect consumers.  Literally, LIES, MISREPRESENTATIONS and even FRAUD in this industry seem RAMPANT!!!  
 
Then you have literally 2 or 3 guys on here, the "highly" respected reviewers that offer their incredibly subjective opinions based on their equipment. music choice and whatever agendas, and the the "jr. head-fiers" just pony up the dough for the next FOM based on that...  
 
WOW!!!  Head-fi?!  More like head-in-the-sand.org to be polite that is...  I have bought plenty of crap HYPED UP on here, just to be duly disappointed.  Want a list?  uDac, uDac-2, Icon Mobile, Earsonics SM3, Grado Gr8, Grado Gr10, Grad HF-2, Grado MS1, Koss Porta Pro, Ray Samuels Shadow, iBasso D4, Amarra, etc.  The disappointment is not based on SQ only, but cost, features, convenience, improvement, etc.
 
At the end, the music I LIKE is AWESOME, no matter what equipment is use to enjoy it!!!