DAC-9

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rbbert

Re: DAC-9
« Reply #40 on: 3 Jun 2011, 06:56 pm »
Well, I guess I'll have to wait to report on the sound; my unit goes back to NuForce for repair.

rbbert

Re: DAC-9
« Reply #41 on: 15 Jun 2011, 06:27 pm »
It's too early to report on the sound, but there are a couple of little idiosyncrasies so far.  1) It doesn't seem to want to work with my PS PowerPlant 300.  2) When I have more than one input source connected, even with signal on only one input, it won't stay locked on the input with signal.

phusis

Re: DAC-9
« Reply #42 on: 16 Jun 2011, 09:04 am »
It's too early to report on the sound, but there are a couple of little idiosyncrasies so far.  1) It doesn't seem to want to work with my PS PowerPlant 300.  2) When I have more than one input source connected, even with signal on only one input, it won't stay locked on the input with signal.

It is my experience and impression that NuForce in general releases a variety of their new products too early. There are simply too many faults for the customers to be confronted with, as if we've unwillingly become part of the "test flying" phase, and it's a shame or even a bit unfair that the ones being eager to invest in the new products upon their immediate release are non-rewarded with faulty items - which is mainly the reason I'm postponing the purchase of the Dac-9. We'll see for how long this is necessitated, but needless to say I hope these "childhood deseases," whatever they are in more detail, will be cured sooner rather than later.

Make no mistake: I'm a continuing and avid supporter of the products by NuForce because of their (progressively) great sound, splendid value, and overall "philosophy," and the above is my only gripe as such.

To conclude: I hope the NuForce team sees some merit in my complaint above, and will seriously consider leaving their new products on the test bench for a little, and not least sufficiently longer until they're put on the market.
« Last Edit: 16 Jun 2011, 03:06 pm by phusis »

nuforce-casey

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Re: DAC-9
« Reply #43 on: 16 Jun 2011, 09:56 pm »
It's too early to report on the sound, but there are a couple of little idiosyncrasies so far.  1) It doesn't seem to want to work with my PS PowerPlant 300.  2) When I have more than one input source connected, even with signal on only one input, it won't stay locked on the input with signal.

1.  The Powerplant is an active switching power supply and there could be unpredictable noise emanating from the unit.

2.  All the DAC9 during the production process are tested with multiple signal cables plugged into.  (a) please note that the BNC and one of the RCA are shared, so they can't be used/plugged in together.

3. If any of the digital cable has a compromised or leaky shielding, it could also cause interference, I would suggest testing with a different set of digital cable to isolate the problem.

nuforce-casey

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Re: DAC-9
« Reply #44 on: 16 Jun 2011, 10:02 pm »
It is my experience and impression that NuForce in general releases a variety of their new products too early. There are simply too many faults for the customers to be confronted with, as if we've unwillingly become part of the "test flying" phase, and it's a shame or even a bit unfair that the ones being eager to invest in the new products upon their immediate release are non-rewarded with faulty items - which is mainly the reason I'm postponing the purchase of the Dac-9. We'll see for how long this is necessitated, but needless to say I hope these "childhood deseases," whatever they are in more detail, will be cured sooner rather than later.

Make no mistake: I'm a continuing and avid supporter of the products by NuForce because of their (progressively) great sound, splendid value, and overall "philosophy," and the above is my only gripe as such.

To conclude: I hope the NuForce team sees some merit in my complaint above, and will seriously consider leaving their new products on the test bench for a little, and not least sufficiently longer until they're put on the market.

We appreciate your feedback and we'll continue to improve.

Nevertheless, we had shipped over 70 DAC9 as of today, so your concerns should've been addressed.  While we have to admit that over the history of Nuforce product launches, we do encounter glitches, but a lot of those glitches are, for example, the power amp has to deal with a wide variety of speakers with varying impedance.  Our first USB DAC faced a wide variety of various computers with varying quality level of the USB buses, those were the challenges.  With DAC9, most of the inputs and outputs are well defined (a line load is simply a line load, and 44.1k S/PDIF signal is a straight forward 75 Ohm signal) there is no ambiguity to cause compatibility problem.


rbbert

Re: DAC-9
« Reply #45 on: 17 Jun 2011, 01:40 pm »
1.  The Powerplant is an active switching power supply and there could be unpredictable noise emanating from the unit.

2.  All the DAC9 during the production process are tested with multiple signal cables plugged into.  (a) please note that the BNC and one of the RCA are shared, so they can't be used/plugged in together.

3. If any of the digital cable has a compromised or leaky shielding, it could also cause interference, I would suggest testing with a different set of digital cable to isolate the problem.

I understand what your points here, but it still means that the DAC-9 is pretty idiosyncratic in its connections.  Hopefully the sound will make it all worthwhile.

worldcat

Re: DAC-9
« Reply #46 on: 18 Jun 2011, 03:03 pm »
how about the sound of the dac any updates??? :nono:

ohlins

Re: DAC-9
« Reply #47 on: 24 Jun 2011, 10:41 am »
Beware of the high output levels...

The balanced output drove my preamp into clipping... I can only use the passive mode..


rbbert

Re: DAC-9
« Reply #48 on: 24 Jun 2011, 01:32 pm »
Beware of the high output levels...

The balanced output drove my preamp into clipping... I can only use the passive mode..

I ordered the "low-output" version for this reason; output levels are a bit higher than typical but easily manageable.  As for the sound, on CD's I think it's better than my Oppo 83SE (which was clearly better by itself compared to into a DACMagic); a bit smoother overall, and what seems like "fuller" bass (whatever that means).  I'm not sure about higher-res formats yet (just not enough careful listening), but I suspect the results will be similar.

phusis

Re: DAC-9
« Reply #49 on: 24 Jun 2011, 01:57 pm »
We appreciate your feedback and we'll continue to improve.

Nevertheless, we had shipped over 70 DAC9 as of today, so your concerns should've been addressed.  While we have to admit that over the history of Nuforce product launches, we do encounter glitches, but a lot of those glitches are, for example, the power amp has to deal with a wide variety of speakers with varying impedance.  Our first USB DAC faced a wide variety of various computers with varying quality level of the USB buses, those were the challenges.  With DAC9, most of the inputs and outputs are well defined (a line load is simply a line load, and 44.1k S/PDIF signal is a straight forward 75 Ohm signal) there is no ambiguity to cause compatibility problem.

Thanks for your response, Casey.

I'm aware of those "compatibility problems" you mention, and that they're part of the challenge, but mostly I'm referring to hard-ware related instances such as, for example, the jitter-issue with the CDP-8 in the Stereophile review, which prompted a new test example where the matter had been corrected, and that further led to a notable upgrade in sonic performance once picked up for its re-review by Stereophile. A matter your team were quick to admit and correct, but still..

http://www.stereophile.com/content/stephen-mejias-june-2011

I could mention other examples that are hardware-related, as the above, but I'm not on a "bashing mission" here. I'm just calling out for a hightened awareness with regard to your products being 100 percent ready for release, so that we'll avoid having to send them back due to whatever issues may arise that could've, and should've been dealt with prior to release.

I have no intention to blow this out of proportion, but I want to be sure that, in this case, the Dac-9 is fully operational, on all cylinders, before going to buy it. A friend of mine is ready to go for a purchase of the Dac-9 as well, so we'll place our tandem order once we believe, or feel assured it's safe.

Best,
M   
« Last Edit: 24 Jun 2011, 05:12 pm by phusis »

John Casler

Re: DAC-9
« Reply #50 on: 24 Jun 2011, 10:26 pm »
Well anyhow; Back to what this DAC sounds like.

First, I am a NuFORCE Dealer (as well as a High End Audio Enthusiast) so take my comments with that in mind.

Second, I demoed the DAC-9 at The Home Entertainment Show a couple weeks ago in a very simple but sophisticated system and it was spectacular.  IMO it bested a couple rather hot DACs right now sonically and aesthetically.

Third, the Volume Control preamp section simply gets out of the way and lets the music through.  As well the gradients on the Volume Control are small enough that you can get the sound pressure levels "just right". :thumb:

Fourth, I just got a real chance to hook it up in my personal system and listen (which I didn't really get to do before the show) and all I can say is WOW!!  Cold and just plugged together, the system is elegantly simple:

OPPO BDP-93 transport>NuFORCE DAC-9>NuFORCE Ref 9 V3 Monoblocs>VMPS RM40 BCSE Speakers.  All wiring is from Alex at WyWires and the same as I used at the show.

Again, all I can say is WOW.  While it sounded good under show conditions too, it didn't sound this good.  If it gets any better (after warm up/which it is doing now) I might have to keep it in the chain and find greener pastures for my $5k preamp/dac. (which I consider one of the best in its price range)

Lots of things being done right with this DAC-9 in the chain;

Bass is deep, tight, clean and powerful.  Mids are realistic and full without being forward.  Highs are crystal clear and present without calling attention to themselves.

Soundstage is wide, tall and 3-D(eep) while images appear across the stage in proportional sized and fully formed sonic holograms.

If I had to "pick a nit" I would maybe say the remote seems a little lightweight, but it works exactly as it should and does the job intended.

If you're not getting the same level of performance, don't hesitate to contact me, as you do need to really read the manual to get the set up right (which I learned the hard way) but can also offer advice on if you need it.




phusis

Re: DAC-9
« Reply #51 on: 24 Jun 2011, 10:56 pm »
Well anyhow; Back to what this DAC sounds like.

First, I am a NuFORCE Dealer (as well as a High End Audio Enthusiast) so take my comments with that in mind.

Second, I demoed the DAC-9 at The Home Entertainment Show a couple weeks ago in a very simple but sophisticated system and it was spectacular.  IMO it bested a couple rather hot DACs right now sonically and aesthetically.

Third, the Volume Control preamp section simply gets out of the way and lets the music through.  As well the gradients on the Volume Control are small enough that you can get the sound pressure levels "just right". :thumb:

Fourth, I just got a real chance to hook it up in my personal system and listen (which I didn't really get to do before the show) and all I can say is WOW!!  Cold and just plugged together, the system is elegantly simple:

OPPO BDP-93 transport>NuFORCE DAC-9>NuFORCE Ref 9 V3 Monoblocs>VMPS RM40 BCSE Speakers.  All wiring is from Alex at WyWires and the same as I used at the show.

Again, all I can say is WOW.  While it sounded good under show conditions too, it didn't sound this good.  If it gets any better (after warm up/which it is doing now) I might have to keep it in the chain and find greener pastures for my $5k preamp/dac. (which I consider one of the best in its price range)

Lots of things being done right with this DAC-9 in the chain;

Bass is deep, tight, clean and powerful.  Mids are realistic and full without being forward.  Highs are crystal clear and present without calling attention to themselves.

Soundstage is wide, tall and 3-D(eep) while images appear across the stage in proportional sized and fully formed sonic holograms.

If I had to "pick a nit" I would maybe say the remote seems a little lightweight, but it works exactly as it should and does the job intended.

If you're not getting the same level of performance, don't hesitate to contact me, as you do need to really read the manual to get the set up right (which I learned the hard way) but can also offer advice on if you need it.

Thanks for sharing your impressions, John! I really appreciate hearing about how you perceive the sound of the DAC-9, as I'm about to invest in it myself. It's also great to learn that the volume control preamp "gets out of the way," and lets the music pass through in what appears a rather unfiltered manner.

Being that you're a dealer of the DAC-9, i.e. NuForce products, perhaps you could enlighten me with regard to the sonic difference between the DAC-9 and the HDP? I'm using the HDP as both DAC and preamp in my system consisting of an HTPC with J River MC16 playback software(playing lossless wav/flac music files from the harddrive), NuForce Stereo 8.5V3, Mundorf Silver/gold IC's and speaker cables and NuForce Impulse USB cable, and Auto-tech's The Mummy speakers(http://www.horns.pl/mummy.html). I'm using USB output/input with the HDP, and intend to use the DAC-9 the same way and as a preamp as well.

What's so important when you speak of getting the most of the DAC-9?

Best,
M


John Casler

Re: DAC-9
« Reply #52 on: 25 Jun 2011, 12:04 am »
Thanks for sharing your impressions, John! I really appreciate hearing about how you perceive the sound of the DAC-9, as I'm about to invest in it myself. It's also great to learn that the volume control preamp "gets out of the way," and lets the music pass through in what appears a rather unfiltered manner.

This is in comparison to having the signal pass through the DAC-9 and then through a preamp.  I would assume some of it is due to a less cluttered signal path with fewer compression connetions and wires.


Quote
Being that you're a dealer of the DAC-9, i.e. NuForce products, perhaps you could enlighten me with regard to the sonic difference between the DAC-9 and the HDP? I'm using the HDP as both DAC and preamp in my system consisting of an HTPC with J River MC16 playback software(playing lossless wav/flac music files from the harddrive), NuForce Stereo 8.5V3, Mundorf Silver/gold IC's and speaker cables and NuForce Impulse USB cable, and Auto-tech's The Mummy speakers(http://www.horns.pl/mummy.html). I'm using USB output/input with the HDP, and intend to use the DAC-9 the same way and as a preamp as well.

I have but a single client in Chile none the less, using a similar set up as yours.  But I don't have that many customers on the "consumer/desktop gear" side, but most of my business is almost exclusively in the "High End Gear" so I have not had the HDP in my system or even in a system I have had the opportunity to evaluate critically.  I do know that my Chilean customer is VERY happy, but he too has not heard the DAC-9.


Quote
What's so important when you speak of getting the most of the DAC-9?

Best,
M

It actually was not so much getting the "most" but actually hooking it up correctly in the first place (although the level of equipment one has and the synergy between components will have significant effect).

That said, two very important things to make sure and do during "set up" are to read the instructions carefully, and make sure and check the "voltage" switch on the rear making sure it is set properly for your country.  I spent a bit of time wondering why I wasn't getting the sound I am now (actually I had NO sound)  because I didn't follow the steps in the manual, the first of which says to "make sure the voltage switch is set for your country". :duh:

Secondly, I also found out that there are TWO Spdif Coaxial inputs (labled 1 and 2 on the rear panel) and the manual tells you they are for DAC front panel INPUTS #3 and #4.  So again if one doesn't read the manual one might be attempting to select #1 or #2, when they should be selecting #3 and #4 on the front panel.

As well one of these inputs "doubles" as a BNC input and they cannot be used simultaneously.

Once those issues are clear in your mind, the machine works like a charm.

To set it to DIRECT you run the volume control up as high as it will go (99 I think) with the remote, and then press the up arrow on the front panel to take it to DIRECT.

I will let my system (just plugged in an hour or so before I posted) warm up and settle in, and see if there is any improvement.  As well I do not have my Power Conditioner in the system and am simply using a good quality Power Strip, so as good as it sounds now, I suspect it could even improve a bit in a day or two.

 

munosmario

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Re: DAC-9
« Reply #53 on: 25 Jun 2011, 12:55 pm »
Thanks for your response, Casey.

I'm aware of those "compatibility problems" you mention, and that they're part of the challenge, but mostly I'm referring to hard-ware related instances such as, for example, the jitter-issue with the CDP-8 in the Stereophile review, which prompted a new test example where the matter had been corrected, and that further led to a notable upgrade in sonic performance once picked up for its re-review by Stereophile. A matter your team were quick to admit and correct, but still..

http://www.stereophile.com/content/stephen-mejias-june-2011


phusis, your statement re notable upgrade in SQ of second review sample is not substantiated in Mejias's review. He (or Stereophile, for that matter) never reviewed the first and second units side by side. So we cannot tell from Mejias's review if second unit sounded better, same, or not as good as first one...all we now is that it measured better in the jitter department and sounded great to Mejias's ears, not the same ears as those of Wes Phillips's--the very experienced reviewer of first unit, who, despite the high jitter measured by John Atkinson, stated that the CDP-8 was the best CD player he had heard. One can surmise that the better jitter measurement should correlate to improved sound quality but, strange at it may sound, that may not be the case here...it appears that jitter has many faces and shows up at different stages of the transport digital data reading, thansport/DAC interconnection, digital cabling quality, and each of the multiple stages of subsequent D to A conversion...and, it seems not all those jitter components are relevant or have same impact in sound quality...so, in this case, since the two units were not compared side by side or were reviewed by the same ears, we will never know about how their SQ compared.

My point is that, after all, if there was any fault in Nuforce sending out a first unit whose jitter did not measure well, they cannot be acused of sending out a unit that sounded bad...on the contrary.

munosmario






« Last Edit: 26 Jun 2011, 03:58 am by munosmario »

phusis

Re: DAC-9
« Reply #54 on: 27 Jun 2011, 03:48 pm »
phusis, your statement re notable upgrade in SQ of second review sample is not substantiated in Mejias's review. He (or Stereophile, for that matter) never reviewed the first and second units side by side. So we cannot tell from Mejias's review if second unit sounded better, same, or not as good as first one...all we now is that it measured better in the jitter department and sounded great to Mejias's ears, not the same ears as those of Wes Phillips's--the very experienced reviewer of first unit, who, despite the high jitter measured by John Atkinson, stated that the CDP-8 was the best CD player he had heard. One can surmise that the better jitter measurement should correlate to improved sound quality but, strange at it may sound, that may not be the case here...it appears that jitter has many faces and shows up at different stages of the transport digital data reading, thansport/DAC interconnection, digital cabling quality, and each of the multiple stages of subsequent D to A conversion...and, it seems not all those jitter components are relevant or have same impact in sound quality...so, in this case, since the two units were not compared side by side or were reviewed by the same ears, we will never know about how their SQ compared.

My point is that, after all, if there was any fault in Nuforce sending out a first unit whose jitter did not measure well, they cannot be acused of sending out a unit that sounded bad...on the contrary.

munosmario

munosmario,

John Atkinson's comment "... one of the highest levels of jitter I have measured, and about 20 times higher than in the best products I have measured" doesn't correspond too well with "NuForce claims that the CDP-8's jitter is "practically non-existent."" As it goes in the follow-up by Stephen Mejias, "The team at NuForce was "embarrassed and chagrined" by the test results."

NuForce obviously didn't intend for the jitter level to be this high with their DSP-controlled design principle(which should've led to the opposite), and so one can only deduce an element of "inadequacy" in the execution of the series which the first test sample was part of. NuForce are definately to be commended for their reliance on ear-testing the CPD-8, but they should've gone one step further and measured the jitter level so to verify whether the intended goal of their design was accomplished. One must assume, had they spotted this measurement shortcoming to begin with, that they'd have corrected the matter, and doing exactly that for no trivial reason.

In light of this your questioning jitter's influence on the sound quality, whether its imprinting is necessarily negatively fused or not(or even for the better), comes largely irrelevant. My issue with NuForce is for them to uphold their initial design goals(as, in this case, with the CDP-8) and trying to avoid other hard- and software related issues that could've been ironed out pre-release. Maintaining their design goals I'm sure is a vital part of my consent to the sound of their products and the upgraded(V2 to V3, etc.) incarnations, and so this points to my appreciation of their deliberate and intended efforts. I'm all in for "elucidation through accident or what wasn't intended," but while questioning or elaborating on the sonic effects of jitter is not without merit I find that in this particular case the issue is irrelevant; my focus is directed at NuForce' intentions backed up with listening tests and measurements, and believing that they make a difference for the better.

I don't see any reason not to "validate" Stephen Mejias impressions of the two test samples in his clearly outlined comparison as one would the intial views of Wes Phillips. Differences aside I'm sure they're both capable of outlining their impressions without succumbing to über-subjective blurriness, and in any case what matters to me is that the same reviewer holds access to a comparative study of the two samples. From my chair and on closer scrutiny it's not entirely clear whether Stephen has had the two test samples for a side by side comparison, but I've read and still reads as if he had - although this is based on assumption and not fact. Maybe you know more than I do.

Please note that I have never stated the first test-sample of CDP-8 to be bad-sounding, or that the initial Stereophile review hinted at this.

Best,
M
« Last Edit: 27 Jun 2011, 05:24 pm by phusis »

nuforce-casey

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  • Posts: 357
Re: DAC-9
« Reply #55 on: 27 Jun 2011, 08:34 pm »
While we are off-topic, let me point out the following issues:

The impact of jitter to sound is still highly debatable, as there are different types of jitters.  To date, the jitter measurements available failed to adequate correlate the measurement with actual audio performance.  So the commonly accepted testings and specifications related to audio equipment do not generally include jitter performance.  The industry consensus is to use AP (Audio Precision) tests results and AP doesn't provide jitter measurement tools.


munosmario

  • Jr. Member
  • Posts: 191
Re: DAC-9
« Reply #56 on: 27 Jun 2011, 08:51 pm »
munosmario,

John Atkinson's comment "... one of the highest levels of jitter I have measured, and about 20 times higher than in the best products I have measured" doesn't correspond too well with "NuForce claims that the CDP-8's jitter is "practically non-existent."" As it goes in the follow-up by Stephen Mejias, "The team at NuForce was "embarrassed and chagrined" by the test results."

NuForce obviously didn't intend for the jitter level to be this high with their DSP-controlled design principle(which should've led to the opposite), and so one can only deduce an element of "inadequacy" in the execution of the series which the first test sample was part of. NuForce are definately to be commended for their reliance on ear-testing the CPD-8, but they should've gone one step further and measured the jitter level so to verify whether the intended goal of their design was accomplished. One must assume, had they spotted this measurement shortcoming to begin with, that they'd have corrected the matter, and doing exactly that for no trivial reason.

In light of this your questioning jitter's influence on the sound quality, whether its imprinting is necessarily negatively fused or not(or even for the better), comes largely irrelevant. My issue with NuForce is for them to uphold their initial design goals(as, in this case, with the CDP-8) and trying to avoid other hard- and software related issues that could've been ironed out pre-release. Maintaining their design goals I'm sure is a vital part of my consent to the sound of their products and the upgraded(V2 to V3, etc.) incarnations, and so this points to my appreciation of their deliberate and intended efforts. I'm all in for "elucidation through accident or what wasn't intended," but while questioning or elaborating on the sonic effects of jitter is not without merit I find that in this particular case the issue is irrelevant; my focus is directed at NuForce' intentions backed up with listening tests and measurements, and believing that they make a difference for the better.

I don't see any reason not to "validate" Stephen Mejias impressions of the two test samples in his clearly outlined comparison as one would the intial views of Wes Phillips. Differences aside I'm sure they're both capable of outlining their impressions without succumbing to über-subjective blurriness, and in any case what matters to me is that the same reviewer holds access to a comparative study of the two samples. From my chair and on closer scrutiny it's not entirely clear whether Stephen has had the two test samples for a side by side comparison, but I've read and still reads as if he had - although this is based on assumption and not fact. Maybe you know more than I do.

Please note that I have never stated the first test-sample of CDP-8 to be bad-sounding, or that the initial Stereophile review hinted at this.

Best,
M

Phusis, you are absolutely right, Mejias did compare the two units side by side. I felt victim to a case of cognitive disonance reacting like a fanclub member. My apologies...in fact, I would like to refer you to my thread on the CDP-8, last post may 25th, 2011, whereby, being puzzeled rather than intending being critical, I expressed a smilar concern to yours relative to the CDP-8' product specifications claims relative to the statement from Jason that they had designed the CDP-8 by ear without paying attention to actual measurements...plus further puzzelment by Wess Phillips's rave review despite the huge jitter messurements. Mejias did not condemn the first version  and was ambivalent of sorts for a while comparing different attributes, at the end stating a prefference base on what subjectibly he felt pleased him the most...one would have expected to find a radical difference beyond spliting hairs between sonic attributes...this prompted me to do some searches about jitter which as you can read in my posts made me realize that jitter measurements are not such a slam dunk when it come to explain SQ....then was when I decidedd to forget any negative feelings and give to Nuforce the credit they deserve in coming out with oustanding SQ products regarding of price (i.e., became the fan club member I mentione above).

If the CDP-8 sounds that good, aren't you curious to hear the new Extreme version of Nuforce's Oppo mod? In his thread about the Oppo's mods, Jason stated:

"BDP-93NE, like the CDP-8, does everything right. Unlike the CDP-8, it is more "tube like" sounding. So it is a matter of taste.

BDP-93NXE brings out the SOUL of the music, whatever that it is playing. A 300 year old cello will sound just like one, a soulful singer's voice will haunt you, you will cry if you hear a sad song, you feet will tap with the music.  In our opinion, this is the best player we have ever heard in our lab.
I personally have not been so moved by music in our demo system until I heard BDP-93NXE yesterday."

That was mid of April, 2011, and by then the DAC9 was already out of the bench ready to go....so, I am definitely curious!!

All the best

munosmario
 
« Last Edit: 28 Jun 2011, 05:51 pm by munosmario »

phusis

Re: DAC-9
« Reply #57 on: 28 Jun 2011, 03:27 pm »
While we are off-topic, let me point out the following issues:

The impact of jitter to sound is still highly debatable, as there are different types of jitters. To date, the jitter measurements available failed to adequate correlate the measurement with actual audio performance.  So the commonly accepted testings and specifications related to audio equipment do not generally include jitter performance.  The industry consensus is to use AP (Audio Precision) tests results and AP doesn't provide jitter measurement tools.

Casey,

I find the above a little puzzling given NuForce's attention towards keeping low jitter values, and being public about it. Perhaps "jitter" has become a popular and more widespread way/say to address a problematic influence on sound quality, and so being "prolific" about keeping low jitter values is a means to be "quantifiable" about a correlation to SQ. It's not that I've come to believe that jitter suppression matters(how would I know?), but more that the focus on this matter(i.e. suppression of jitter) by the manufacturer has indicated its importance - hence my reliance on your(NuForce's) initial reaction("embarrassed and chagrined") to JA's jitter measurements, and your taking action towards correction of the matter. By all account Stephen Mejias heard a difference, and, to his ears, eventually for the better in the updated sample. Others might disagree on this verdict, I guess. However, if the updated version of CDP-8 is the only version from now on in production, one would believe in the preference at least from the manufacturer...

Sorry if this has become a tiresome matter, and drawn focus in a different direction from that of the thread's subject, the DAC-9. DAC-9 has my main interest, but the BDP 93NXE has suddenly, by way of munosmario, come to my attention as well. In fact I would be more than interested to learn of some views on the sonic differences between the two.

Best,
M
« Last Edit: 28 Jun 2011, 10:05 pm by phusis »

rollo

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Re: DAC-9
« Reply #58 on: 28 Jun 2011, 03:37 pm »
  Details details. When one puts all the pieces together the final result [ product] is the tell tale. So far the response overall is very positive.
  Jitter is important but there are many other contributing factors to great CD sound. For me when inserting a new piece in the system there is only one criteria. Does it sound better to me ? If so it stays if not it goes.
  Really guys don't get hung up about one issue it is the overall performance that matters.



charles

nuforce-casey

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Re: DAC-9
« Reply #59 on: 28 Jun 2011, 05:45 pm »
Casey,

I find the above a little puzzling given NuForce's attention towards keeping low jitter values, and being public about it. Perhaps "jitter" has become a popular and more widespread way/say to address a problematic influence on sound quality, and so being "prolific" about keeping low jitter values is a means to be "quantifiable" about a correlation to SQ. It's not that I've come to believe that jitter suppression matters(how would I know?), but more that the focus on this matter(i.e. suppression of jitter) by the manufactorer has indicated its importance - hence my reliance on your(NuForce's) initial reaction("embarrassed and chagrined") to JA's jitter measurements, and your taking action towards correction of the matter. By all account Stephen Mejias heard a difference, and, to his ears, eventually for the better in the updated sample. Others might disagree on this verdict, I guess. However, if the updated version of CDP-8 is the only version from now on in production, one would believe in the preference at least from the manufactorer...

Sorry if this has become a tiresome matter, and drawn focus in a different direction from that of the threads subject, the DAC-9. Named D/A converter has my main interest, but the BDP 93NXE has suddenly, by way of munosmario, come to my attention as well. In fact I would be more than interested to learn of some views on the sonic differences between the two.

Best,
M

Jitter measurements are reflections of our design goal.  But good looking plots are not what we are after.

With CDP-8, we basically slaves the CD data to the DAC, rather than slaving the DAC to the CD transport.  The 'improvement' in the 2nd CDP8 sample to Stereophile had no change to the original design architecture, but simply modifying a different analog grounding point. Which implied that the measured jitter was not from the data but rather from interference (at very low level) below -90dB, which you can refer to the THD measurement and the spectrum plot.

In the BDP-93 NXE, the idea being that the BD audio data are interleaved with video data, hence the inherent high jitter when the audio data is recovered.  The core idea is to run a completely asynchronous clocked data to the DAC.  The jitter measurement reflects what we did. 

In fact, you can't really 'calculate jitter', the plot is a spectrum plot of a special signal: a 11.025kHz with a 221Hz at 1-bit depth blended in. 
« Last Edit: 28 Jun 2011, 11:09 pm by nuforce-casey »