Jitter vs no-Jitter

[bibo01]

Out on a limb but committed, I can definitely hear a difference between the two tracks. I wish I knew what the instruments sound like live, though. I think the flute on A1 is clearer and a little bit "thinner". Attacks are cleaner and notes are a bit better defined. A2 sounds a bit muddy & fat by comparison, and is not quite so clearly a flute until a few notes have come out of it. But the tone of the flute A2 does sound more "sinusoidal" to me - so does it have less odd order harmonic content in its native tone? If so, then the jitter is in A1 and it's adding odd order harmonic distortion. But through my earbuds at work, A1 sounds more like a flute than A2.

 

The harpsichord is closer on the two than the flute, but it sounds like a better instrument on A1 than on A2 - the low register is a little richer and the pluck a bit cleaner. So I'm sticking with A2 as the jittery one.

Thanks.

So in the pool you should vote - A1

 

Note:

unfortunately the site did not allow the pool to have the full question and it might be confusing for some users

[bluesman]

Thanks. So in the pool you should vote - A1

?? I thought we were supposed to try to identify the jittery one, which is why I selected A2 in the poll. I may not be the only confused one, so clarity would be appreciated.

 

David

[徐中銳]

I'm just seeing a lot of "tests" these days that are purported to measure jitter, but are really measuring something else. I think jitter IS important, but if your doing jitter tests I think you actually need to measure jitter not something else.

 

John S.

 

Of recent products, recalling « jitter graph » from Marantz Japan's NA6005 Network Audio Player :

Click marantz.jp/jp/img/NA6005/NA6005_11.png for its original 3300 x 1429 pixels

 

UK listing description :

Advanced Jitter Reduction System

« Working in concert with the CS4398 D/A converter, the NA6005's jitter reduction circuit features a dedicated timing data re-clocking system that eliminates distortion caused by poor timing stability in the incoming audio data stream. »

 

And for its CA discussion Thread

[bibo01]

?? I thought we were supposed to try to identify the jittery one, which is why I selected A2 in the poll. I may not be the only confused one, so clarity would be appreciated.

 

David

 

This is perhaps a fault on my part because it is my first pool.

However, if you re-read my initial post, I am asking "to recognize DAC no.1 with less jitter".

 

If you have expressed your vote already, do not worry I will keep it mind in the final count.

[bibo01]

Thanks for that explanation - it makes much more sense of the test as I was contemplating that the test was just two different DACs i.e everything different & this would negate the validity of the test in many people's mind & probably prevent many people from engaging in it.

 

I think it would be wise to highlight what you have just posted in the different forums you have posted the poll

 

From the graphs the base of the main signal has a much wider spread than the other - which signifies significant close-in jitter before consideration is even given to the side spurs.

 

The "normal" jitter test is the Jtest - where a main signal tone (usually 24KHz) is combined with another signal which toggles the low-order bit (LSB). This was originally designed to test the data induced jitter inherent in SPDIF receivers but is still used as a rough jitter test where no SPDIF receivers are involved i.e. USB receivers in computer audio

 

The Jtest with combined signal is not necessary, at least in this case. We will discover it in the end.

[soss]

I suggest starting this whole thing over. You got have the actual question in the first post.

 

 

So are we suppose to pick the track we think has "high jitter" or the track that we think has "low jitter"????????

 

Thanks.

[sandyk]

Dennis

Would you please PM me, as I keep getting the attached message when attempting to send you a PM.

Alex

 

Fatal error: Call to undefined function fetch_tag_list() in /var/www/mobiquo/include/function_push.php on line 414

[bibo01]

I suggest starting this whole thing over. You got have the actual question in the first post.

 

 

So are we suppose to pick the track we think has "high jitter" or the track that we think has "low jitter"????????

 

Thanks.

There are 2 DACs: one with low jitter and one (damaged) with high jitter

In my question you are supposed to pick the DAC, and therefore the track, with low jitter.

[Sal1950]

I THOUGHT I could hear what sounded like a harpsichord playing softly in the background more clearly on A2. We'll see how the poll comes out.

(Using Emotiva DC-1 into Senn HD 650s)

[mmerrill99]

I do think that the poll is flawed as it's assuming that we all have the same perception of how jitter sounds & this is a great mistake, I believe. As we can see with the posts already, many are interpreting what they hear in different ways as regards the sound of jitter.

 

I believe a better poll would be to determine if people can hear a difference between the two tracks & the easiest way would be to post links to 3 tracks, two of which are the same & allow people to identify which two tracks are the same

[bibo01]

I do think that the poll is flawed as it's assuming that we all have the same perception of how jitter sounds & this is a great mistake, I believe. As we can see with the posts already, many are interpreting what they hear in different ways as regards the sound of jitter.

 

I believe a better poll would be to determine if people can hear a difference between the two tracks & the easiest way would be to post links to 3 tracks, two of which are the same & allow people to identify which two tracks are the same

 

If as you say I had added a third track equal to one of the two files I posted, anybody with a simple software would have made a comparison and have solved the mystery in less than 2 minutes.

 

One just has to listen and decide according to one's own perception.

[mmerrill99]

If as you say I had added a third track equal to one of the two files I posted, anybody with a simple software would have made a comparison and have solved the mystery in less than 2 minutes.

 

One just has to listen and decide according to one's own perception.

OK, just trying to help.

[bluesman]

If as you say I had added a third track equal to one of the two files I posted, anybody with a simple software would have made a comparison and have solved the mystery in less than 2 minutes.

Have some faith! Maybe a few would have "cheated", but most of us would have taken the audibility test - that's where the fun is.

[Sal1950]

Just forget the jitter issue and vote for the one that sounds best to you. The results will answer the jitter question. And don't make the same mistake I did and post how you voted, that can only effect how others vote and remove any chance of a least a semi-blind test.

[sandyk]

Just forget the jitter issue and vote for the one that sounds best to you. The results will answer the jitter question.

 

No, they will not. Apparently quite a few people prefer the effect of a little "Jitter", as Barrows discussed in a very informative post about the audible effects of "Jitter" some time back.

The lack of participation in a forum with such a high number of members also suggests perhaps a lack of confidence in the methodology used, or perhaps for some who have downloaded the files, the type of material used may not be too helpful for them. Add to that, in the poll results so far, 2 members appear to have made a mistake due to unclear directions initially, and the results so far taking that into consideration, appear to be meaningless.

[mrvco]

At work w/ headphones. I can't say I hear any difference. I was thinking A1 might be a tad better maybe, but I was starting to get a headache from flipping back and forth.

[bluesman]

At work w/ headphones. I can't say I hear any difference. I was thinking A1 might be a tad better maybe, but I was starting to get a headache from flipping back and forth.

If better means closer to the live sound of those specific instruments, it's impossible to determine that one reproduction is better than the other without knowing what they sound like live when played by the same players. I agree with you that A1 sounds a little more like real instruments. But we're on a bit of a fool's errand here.

 

Even the material from which a flute is made is not inherently obvious to top players - the sound is largely in their embouchure. There's a story that Jean-Pierre Rampal once demonstrated this during a legendary interview in which he picked up a silver flute and said to the interviewer: "This is the sound of a silver flute" and played a phrase. Then he said "This is the sound of a gold flute", and he played the same phrase with a different tone on the same flute. And James Galway said in a PBS interview that he simply could not tell from listening to a recording whether he was playing one made of gold, silver or other material.

 

So I'm not sure how we can listen for accurate reproduction when we have no reference - but I'm sticking with A1 as the more real-sounding of the two....just because.

[Sal1950]

No, they will not. Apparently quite a few people prefer the effect of a little "Jitter", as Barrows discussed in a very informative post about the audible effects of "Jitter" some time back.

The lack of participation in a forum with such a high number of members also suggests perhaps a lack of confidence in the methodology used, or perhaps for some who have downloaded the files, the type of material used may not be too helpful for them. Add to that, in the poll results so far, 2 members appear to have made a mistake due to unclear directions initially, and the results so far taking that into consideration, appear to be meaningless.

 

So how many members do you think have any idea what jitter sounds like and what to listen for? I don't.

Sady then I feel this poll is useless. Those who have posted here talk about listening for sound quality.

[sandyk]

Sal1950

 

I reposted the attached from C.A. member Barrows in another forum, as it complemented the findings of both John Kenny and myself.

Unfortunately, the original C.A. link no longer works.

 

Alex

 

Extract from a reply by "barrows" at the attached link.

Alex

 

http://www.computeraudiophile.com/f8-general-forum/new-dichotomy-async-vs-non-async-dacs-2748/

"OK, now our discussion is going to get a little controversial, please accept here that I am now just thinking out loud and offering an opinion. Do we want the lowest possible jitter? For me the answer is clearly yes; I have been involved in listening tests of prototype products, and my experiences in those tests indicated that every time we lowered jitter, sonic performance improved. The tests I am referring to kept every aspect of design the same, except for the changes that lowered jitter. These tests were done in a reference system that was relatively well set up, fairly high resolution, and pretty close to neutral tonally. The thing is, I could imagine some people preferring the sound of higher jitter, in some systems. In other words, a low jitter source, if one is used to hearing higher jitter levels, may point out what I would call problems in a system. It appears to me, that some levels/spectrums of jitter may have a euphonic result in some systems. To me, in a good system, the results of lowering jitter are increased detail retrieval (as evidenced by image specificity, decays, more complex harmonic portrayals) accompanied by greater listening ease. Higher levels of jitter result in a hazy sound, obscuring these same lower level details to some extent, but sometimes higher jitter levels also result in the appearance of a larger, billowing, soundstage, that can be somewhat impressive at first listening. I can certainly imagine a system, that is already on the bright/hard side, where a listener might be very impressed by the sound of a higher jitter source and the little bit of haze it brings, along with a big, billowy, soundstage.

I think as listeners/consumers we should demand sonic excellence for the products we purchase, and part of that excellence will be produced by low jitter sources (and hopefully higher resolution music files). The good news is, we have a lot of low jitter choices in computer interfaces right now: Weiss' Firewire and Metric Halo's Firewire products, Wavelength and Ayre's USB products, and Linn's network players are just the tip of the iceberg of high quality, very low jitter, computer audio interfaces that are well engineered and offer great sound. The only way a SPDIF/AES input DAC can offer similar jitter levels is by adding jitter reduction circuitry: ASRCs or reclockers, and personally I find those solutions at the very best less elegant, at the worst sonically compromised, to getting the interface right in the first place.

I have no idea whether there is any reason to consider factors other than jitter when speaking about the sonic performance of different computer audio interfaces. To my mind it is hard to fathom how different interfaces could affect sound (assuming they are all bit perfect) outside of the influence of jitter. I would love to hear if any computer design engineers have any ideas of additional effects on sonic performance produced by different interfaces."

 

http://www.computeraudiophile.com/content/New-Dichotomy-Async-vs-Non-async-DACs#comment-29419

 

Post by jkeny on Dec 11, 2011 at 4:11am

 

OK, Franz, I'm glad you started this thread as I felt the last thread had turned a corner & was about to get interesting when it was deleted. I'm also sorry that my last post went AWOL with the thread because I felt it relevant to a way forward in all of this.

 

First of all let me state that my question "how do you eliminate jitter" was not really a question as I know that you can't eliminate it - you can probably, with difficulty reduce it to levels where it is unimportant & other factors become more prevalent. (BTW, let's not get into the debate about 100s of nS audibility threshold of jitter - this is incorrect) I'm pretty sure that the real jitter level that is audible is down in the double digit pS level & may even be single digit pS.

 

Now let's state what jitter sounds like. Best to quote Bob Katz & add my own points to his:

 

This is a quotation from Bob Katz, well known recording & audio mastering engineer posted here http://www.digido.com/audio-faq/j/jitter-better-sound.html

 

After an engineer learns to identify the sound of signal-correlated jitter, then you can move on to recognizing the more subtle forms of jitter and finally, can be more prepared to subjectively judge whether one source sounds better than another.

 

Here are some audible symptoms of jitter that allow us to determine that one source sounds "better" than another with a reasonable degree of scientific backing:

 

It is well known that jitter degrades stereo image, separation, depth, ambience, dynamic range.

 

Therefore, when during a listening comparison, comparing source A versus source B (and both have already been proved to be identical bitwise):

 

The source which exhibits greater stereo ambience and depth is the "better" one.

 

The source which exhibits more apparent dynamic range is the "better" one.

 

The source which is less edgy on the high end (most obvious sonic signature of signal correlated jitter) is the "better" one.

 

And a reply:

The better one, and it is better, is also easier to listen to. . . less fatiguing. I would also add to this that the low end just "feels" bigger and more solid. This is perhaps a psychoacoustic affect more than a measurable one. It may be that the combination of a less edgy high end and greater depth and width makes the bass seem better.

 

All of this makes sense if thought of in terms of timing (that is what we're talking about isn't it ;-]). With minimal jitter nothing is smeared, a note and all its harmonics line up, the sound is more liquid (a term probably from the "audiophile" crowd but one which accurately describes the sound none the less), and images within the soundstage are clearly defined.

 

 

Now some extra points:

- listener fatigue is reduced or completely eliminated

- the sound can be turned up higher without any distortion being evident

- the sound can also be turned down lower & the full dynamics are still retained but at a lower volume

 

Hope this helps.

 

Next I'll address some of what Franz states

 

 

 

 

 

 

Read more: Jitter chatter | Rock Grotto

[bibo01]

OK, just trying to help.

 

Don't you worry, help is appreciated.

We are hear to openly discuss

[徐中銳]

Of recent products' date=' recalling [/font']« jitter graph » from Marantz Japan's NA6005 Network Audio Player :

Click marantz.jp/jp/img/NA6005/NA6005_11.png for its original 3300 x 1429 pixels

 

UK listing description :

Advanced Jitter Reduction System

« Working in concert with the CS4398 D/A converter, the NA6005's jitter reduction circuit features a dedicated timing data re-clocking system that eliminates distortion caused by poor timing stability in the incoming audio data stream. »

 

And for its CA discussion Thread

 

I'm just seeing a lot of "tests" these days that are purported to measure jitter, but are really measuring something else. I think jitter IS important, but if your doing jitter tests I think you actually need to measure jitter not something else.

 

John S.

 

And recalling these Jitter graphs too, of their (2013 release of) NA-11S1 to (2012's) SA-11S3 :

[jabbr]

Ha! This is hard:) I can clearly hear a difference. On one track, there are some high notes which disturb me -- so either they are really there (I'm not a big flute fan) or else represent the effects of jitter -- not being a flute/harpsichord "expert" makes this more difficult than I expected. I picked the one which I liked better.

 

Back to Coltrane (old) and Cecile (new)...

[bibo01]

Ha! This is hard:) I can clearly hear a difference. On one track, there are some high notes which disturb me -- so either they are really there (I'm not a big flute fan) or else represent the effects of jitter -- not being a flute/harpsichord "expert" makes this more difficult than I expected. I picked the one which I liked better.

 

Back to Coltrane (old) and Cecile (new)...

 

Thanks for participating.

[RedFuneral]

My system tops out at 44.1K so I'm listening on consumer headphones direct from my PC. The first rendition is able to keep my attention all the way through whilst when listening to the second I found myself tuning it out. So my conclusion is either that A1 has less jitter or this bottom-barrel headphones system benefits from a little distortion.

[Don Hills]

... Even the material from which a flute is made is not inherently obvious to top players - the sound is largely in their embouchure. ...

 

 

The article linked below reads like any audiophile investigation into the sound of audio components. Sighted differences disappearing when blind tested, and Lord Rayleigh's famous words " What we cannot measure, we do not know". He also uses many of the same tools used in our familiar fields of audio analysis, and asks many of the same questions.

 

Flute Tone Investigations - Intro

 

Edit: The link to Gregor Widholm's paper in the above intro is broken. This works:

 

Wall material and the sound of the flute - Institute of Music Acoustics (Wiener Klangstil)