Jitter vs no-Jitter

[4est]

Actually, what you said was that thinking anything other than Peter's approach as correct was akin to hallucinating. Maybe it is just me, but I am tired of your divisive obj/sub pigeonholing and putting words in others mouths. Speak for yourself, and let others do the same.

I find it interesting and curious that whenever I post something like this ya'll have to reply with mis-quotes and outright lies that the truth of which is obvious to anyone that read the thread. I neither "mocked ITU standards" nor "rejected what you believe to be real science"

I simply said I find the test criteria laid down by Peter Aczel sufficient IMHO.

So if your going to reply to me use truthful quotes of my statements.

In any case we all know that the position of the subjectives here is that ALL ABX-DBT tests are unreliable and only your golden ears can be counted on to reveal the truth, just as long as your opinions never have to be put to any controled tests

 

bibo01, Thanks for all the hard work and time you invested in putting this test together!

[Jud]

I thank Tom "Gefrusti" for his indispensable help to the poll

 

-----------------------

I was not aware of the solution before the poll.

As reported from the file I mentioned above, the solution is:

 

DAC A1 = jitter OFF.

 

DAC A2 = jitter On

 

-----------------------

 

What is interesting in my view is that the difference, which everyone was aware of before the test, was not at all easy to spot.

The majority of the voters preferred the "jittered" track.

In the Italian forum NextHardware where I was running the same poll, I also voted A2

 

Thank you very much, bibo01. I would not have expected different results than the ones you got. I regret that I did not get around to doing the test, but I'm fairly certain I would have had no better idea than anyone else.

 

A question for you: After a couple of these tests, are you yourself able to hear any characteristic sound that jitter will produce?

[bluesman]

After a couple of these tests, are you yourself able to hear any characteristic sound that jitter will produce?

I think I can, as I described in my first post.

 

Out on a limb but committed, I can definitely hear a difference between the two tracks...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... 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.

Let's assume for the moment that I could do this again several times (i.e. it wasn't just sunspots or what I ate that day that colored my thinking) and that the only difference between the two is jitter. If both are true, then jitter audibly blurs transients and adds spurious harmonic content (as opposed to random noise). Something made an audible difference, and that difference was (and remains) consistent over several auditions:

 

• A1 sounds more like a flute than A2
  
• Attacks are cleaner and notes are a bit better defined. A2 sounds a bit muddy & fat by comparison.
  
• The harpsichord...sounds like a better instrument on A1 than on A2 - the low register is a little richer and the pluck a bit cleaner.
  

Of course, if I couldn't do it again, I'm with Emily Litella...

[Jud]

bluesman: What I would prefer, if you're up for it (and anyone else who is), rather than doing it again, is to listen closely to one file until you feel you are familiar with its sound, and then at another time do the same with the other. If after that you feel you are able to say anything more about the characteristic sound of the file with jitter, I'd be interested to know.

[bibo01]

Thank you very much, bibo01. I would not have expected different results than the ones you got. I regret that I did not get around to doing the test, but I'm fairly certain I would have had no better idea than anyone else.

 

A question for you: After a couple of these tests, are you yourself able to hear any characteristic sound that jitter will produce?

I was one of the 6 voters on NextHardware who chose A2, as I did not know the result before hand.

Obviously I am not fully capable to hear any characteristic sound that jitter will produce.

To be honest - I am not trying to "save" myself - in my first hearing I preferred A1; then the next day, listening with my partner, I preferred A2. Preferring A2, however, it left me with a doubt. In both cases, for example, I preferred the first song I heard . Then, when my friend Tom told me that in an ABX test he was not able to discern a difference through headphone, I realized it was not at all easy to distinguish the tracks in terms of jitter and no-jitter.

When the difference between tracks is not so easy detectable, in my view a person can often mistake a fat sound with a rich one and viceversa.

[bluesman]

bluesman: What I would prefer, if you're up for it (and anyone else who is), rather than doing it again, is to listen closely to one file until you feel you are familiar with its sound, and then at another time do the same with the other. If after that you feel you are able to say anything more about the characteristic sound of the file with jitter, I'd be interested to know.

Actually, I've been doing that because I'm really curious to know what's real to me and what's my imagination. I've done this with multiple earbuds, my trusty Sony MDR-V150s, my AKG 701 QJs and my Rogers LS3/5as, using each for several sessions over a few days. My initial descriptions are still accurate. The flute simply sounds more like a real flute - the tone is better balanced, the attack is cleaner, and there seems to be less harmonic content. On A2, the flute is a bit fuller and rounder as though it got a 2 or 3 db EQ boost from about 200 to 600 Hz. The breathy attacks are less well defined, and it sounds a bit more like a sampled flute than a live one.

 

The sound of the harpsichord is more natural as well. The midrange harmonics are smoother (which suggests to me that there's less odd order harmonic neo-content or distortion). Again, it sounds more like a real harpsichord than A2, which sounds a bit like a very good electronic keyboard's harpsichord voice. The pluck of each note is also a bit cleaner and clearer on A1.

 

These differences are not huge to me, but they seem to be clearly and consistently audible. I may enlist my wife's help in a blinded effort one Sunday - I'm really curious as to whether I'm hearing or hallucinating.

 

David

[christopher3393]

Actually, what you said was that thinking anything other than Peter's approach as correct was akin to hallucinating. Maybe it is just me, but I am tired of your divisive obj/sub pigeonholing and putting words in others mouths. Speak for yourself, and let others do the same.

 

+1

[esldude]

bluesman: What I would prefer, if you're up for it (and anyone else who is), rather than doing it again, is to listen closely to one file until you feel you are familiar with its sound, and then at another time do the same with the other. If after that you feel you are able to say anything more about the characteristic sound of the file with jitter, I'd be interested to know.

 

Well, first let me preface my comment by saying you are assuming someone who picked correctly heard a difference when they may have just gotten lucky. Plus this test wasn't so much a test to see if there was a difference as it was for people to pick what they thought was the better sound. People's preferences vary, and this was more of a preference test. The assumption being that no jitter would be the better sounding file. That actually may or may not be the case. The food industry does preference testing. It is a valid method itself though for different purposes. In preference testing you usually aren't allowed to choose no difference.

 

If we assume the files were audibly different, the test results over the three forums it was posted in show a general preference for the jittered file.

 

Now as someone who chose correctly the low jitter file I will tell you how it sounded to me. Simply cleaner and clearer, and more real. The A2 file sounded warm, but warm in a fuzzy lower fidelity way.

 

Looking at comments that were made that seems more or less to be a consensus. One is cleaner (or crisper if you don't like it) and one is warmer (or fuzzy if you don't like it). And this is allowing several dubious assumptions to pass without scrutiny.

 

The assumption made by audiophiles repeatedly is they can discern the higher quality higher fidelity file and they will prefer the higher fidelity. I don't at all believe this is the case. Audiophiles can be very discerning, but preferences vary and fidelity is not always preferred.

[Jimmypowder]

I only get jitter on the shitter .

[bluesman]

Well, first let me preface my comment by saying you are assuming someone who picked correctly heard a difference when they may have just gotten lucky. Plus this test wasn't so much a test to see if there was a difference as it was for people to pick what they thought was the better sound.

This may or may not matter to you, but I've been a professional musician since 1960 - I paid dues to Local 77 of the AFM for about 35 years after joining in 1969. I know what most instruments sound like, live and recorded many ways on many systems in many studios. My first recording date was at Virtue Studios in Philly in 1959 (yes, I was 13) and I recorded as a sideman at Sigma Sound Studios (look it up if you don't know it - Sigma was as good as it gets for most of its life, and many hits were made there although I was on less distinguished efforts). I've played thousands of dates from weddings to blues festivals to classical, the last of which was last Friday night. The next two are this Friday (at the Reading Terminal Market in Philly) and Saturday (at the Fenix Lounge in Phoenixville, PA).

 

I don't think I'm basing this one on preference and I don't think it was just luck. YMMV.

[esldude]

This may or may not matter to you, but I've been a professional musician since 1960 - I paid dues to Local 77 of the AFM for about 35 years after joining in 1969. I know what most instruments sound like, live and recorded many ways on many systems in many studios. My first recording date was at Virtue Studios in Philly in 1959 (yes, I was 13) and I recorded as a sideman at Sigma Sound Studios (look it up if you don't know it - Sigma was as good as it gets for most of its life, and many hits were made there although I was on less distinguished efforts). I've played thousands of dates from weddings to blues festivals to classical, the last of which was last Friday night. The next two are this Friday (at the Reading Terminal Market in Philly) and Saturday (at the Fenix Lounge in Phoenixville, PA).

 

I don't think I'm basing this one on preference and I don't think it was just luck. YMMV.

 

Well I chose the same as you. I am not a musician. I do some recording, but haven't until recently. So what does it mean?

 

I am not trying to denigrate your credentials or experience. Just attempting to be realistic about what the results are worth and what they mean. I don't think I was lucky either.

[Jud]

Well, first let me preface my comment by saying you are assuming someone who picked correctly heard a difference when they may have just gotten lucky. Plus this test wasn't so much a test to see if there was a difference as it was for people to pick what they thought was the better sound. People's preferences vary, and this was more of a preference test. The assumption being that no jitter would be the better sounding file. That actually may or may not be the case.

 

Your ESP is on the fritz, my friend. I made no such assumptions, and in fact it was bibo01 I asked in the first instance, who hadn't previously indicated whether or not he picked the correct file. My questions were an attempt to get people to describe what they felt they were hearing from the jittered file after some amount of repeated exposure. In other words, I'd like to get the best descriptions I can of the "sound of jitter."

 

If we assume the files were audibly different, the test results over the three forums it was posted in show a general preference for the jittered file.

 

Yes, again not surprising.

 

Now as someone who chose correctly the low jitter file I will tell you how it sounded to me. Simply cleaner and clearer, and more real. The A2 file sounded warm, but warm in a fuzzy lower fidelity way.

 

Looking at comments that were made that seems more or less to be a consensus. One is cleaner (or crisper if you don't like it) and one is warmer (or fuzzy if you don't like it). And this is allowing several dubious assumptions to pass without scrutiny.

 

That's helpful - thank you for your description. If you feel that further listening might provide additional descriptive information and care to provide it, that would also be appreciated.

 

The assumption made by audiophiles repeatedly is they can discern the higher quality higher fidelity file and they will prefer the higher fidelity. I don't at all believe this is the case. Audiophiles can be very discerning, but preferences vary and fidelity is not always preferred.

 

For the vast majority of A/B comparisons, I agree.

 

This may or may not matter to you, but I've been a professional musician since 1960 - I paid dues to Local 77 of the AFM for about 35 years after joining in 1969. I know what most instruments sound like, live and recorded many ways on many systems in many studios. My first recording date was at Virtue Studios in Philly in 1959 (yes, I was 13) and I recorded as a sideman at Sigma Sound Studios (look it up if you don't know it - Sigma was as good as it gets for most of its life, and many hits were made there although I was on less distinguished efforts). I've played thousands of dates from weddings to blues festivals to classical, the last of which was last Friday night. The next two are this Friday (at the Reading Terminal Market in Philly) and Saturday (at the Fenix Lounge in Phoenixville, PA).

 

I don't think I'm basing this one on preference and I don't think it was just luck. YMMV.

 

I think your experience could have helped here. I also think you'll be interested (if I ever publish my intended article, or failing that, publish the links to the sources I've been looking at) in how surprisingly little a musical background may help in some auditory tests you'd think would be pretty simple for such folks.

[bluesman]

Well I chose the same as you. I am not a musician. I do some recording, but haven't until recently. So what does it mean?

I think it means that skilled listeners with enough exposure to live musical instruments to truly know what they sound like can hear audible differences like those we're discussing, if they exist. But there's a lot of psychoacoustics research showing that the less discriminating listener is often "fooled" by extraneous factors. For example, there are many studies showing that people routinely choose as "better" otherwise identical reproduction (equipment, source etc) that is simply 1 db louder than the comparator. Adding a bit of white noise to a source results in listeners' reporting "better high frequency response", too.

 

I'm sure some prefer the sound of the jittery DAC because it does make the flute sound fuller and smoother, even though it's fuller and smoother than the instrument sounds in person. A real flute being played next to you can even sound a bit harsh and breathy compared to the recorded flutes that serve as reference for most. So if you're used to a softer flute sound on your recordings, the sound of a real one might well be perceived as shrill. Similarly, the plucking of a harpsichord string causes a "spectral splash" of high order harmonics that could be blurred (if my interpretation is correct) by jitter, making the recording of the instrument sound less "tinkly" for lack of a better descriptive term.

 

I'd love to do this test with pizzicato strings in the scherzo (3rd movement) of Tchaikovsky's 4th. If my concept is correct, there should be a clearly audible difference as all those strings are plucked in unison - jitter should blur the individual instruments and make each note sound like it was plucked on a few huge violins plus a few huge violas plus a few huge cellos instead of a string section.

[Sal1950]

Read Lie #4

The Ten Biggest Lies in Audio - ecoustics.com

 

Yes it appears that anybody who uses the phrase "controlled testing" &/or DBT think that they are on the side of science & science is backing them - nothing could be further from the truth - it's the epitome of irony.

 

We are, do you call "it sounds good to me" science? LOL

Peter laid out all you need to know to run reasonably valid tests

But drink the KoolAid and enjoy your cult approach.

 

I find it interesting and curious that whenever I post something like this ya'll have to reply with mis-quotes and outright lies that the truth of which is obvious to anyone that read the thread. I neither "mocked ITU standards" nor "rejected what you believe to be real science"

I simply said I find the test criteria laid down by Peter Aczel sufficient IMHO.

So if your going to reply to me use truthful quotes of my statements.

In any case we all know that the position of the subjectives here is that ALL ABX-DBT tests are unreliable and only your golden ears can be counted on to reveal the truth, just as long as your opinions never have to be put to any controled tests

 

bibo01, Thanks for all the hard work and time you invested in putting this test together!

 

Actually, what you said was that thinking anything other than Peter's approach as correct was akin to hallucinating. Maybe it is just me, but I am tired of your divisive obj/sub pigeonholing and putting words in others mouths. Speak for yourself, and let others do the same.

 

LOL, There ya go again, putting words in my mouth and making things up as you please. If you can't counter without making honest statements and quotes please don't bother, it only makes you look foolish. I'll say no more since I'll only be attacked with more "hallucinations".

[esldude]

Well for those wanting more files with jitter in them to learn what it might sound like, Mitchco provided this link:

 

jitter_1

[bluesman]

I also think you'll be interested (if I ever publish my intended article, or failing that, publish the links to the sources I've been looking at) in how surprisingly little a musical background may help in some auditory tests you'd think would be pretty simple for such folks.

There's a lot of interesting work in this area, Jud! Kraus and Chandrasekaran (in Nature Reviews, Aug 2010) reported good evidence that "...music training leads to changes throughout the auditory system that prime musicians for listening challenges beyond music processing. This effect of music training suggests that, akin to physical exercise and its impact on body fitness, music is a resource that tones the brain for auditory fitness." More specifically,

"[d]ifferences between musicians and non-musicians in the ability to extract relevant information from the incoming signal have been studied using the mismatch negativity (MMN) as an index. An MMN occurs when the brain detects a change (or violation) in a predictable auditory stream (for example, a rarely presented ‘oddball’ in the context of a frequently occurring and predictable sound event). Detection of a change in pattern requires a strong neural representation of the predictable stimulus. The magnitude of the MMN response has been shown to closely reflect a person’s auditory perceptual ability, that is, a larger MMN reflects a greater perceived distance between two sounds.

Musicians show stronger MMN to musical stimuli, to linguistic pitch contours (a transfer effect) and to abstract sound features compared with non-musicians.

This indicates that music training may promote an efficient top-down feedback system that is continuously (and automatically) engaged to extract and robustly represent regularities in the auditory system. Consistent with this idea,

induced oto-acoustic emissions have revealed evidence that there are stronger efferent (top-down) effects on cochlear biomechanics in musicians than in non-musicians.

"

 

I suspect strongly that MMN occurs in our jitter test when the flute doesn't sound like the listener expects it to sound. So for a musician, the jittery one causes the MMN while for the non-musician the one without jitter is the "mismatched" one that doesn't jive with what the listener believes is the correct sound of a flute. And if the above research conclusions are correct, the non-musician will be less sensitive to the MMN, which would logically result in a preference for the jittery one but with less certainty and consistency.

 

I look forward to reading whatever you have. When I was a resident, I wanted to try to develop an animal model for absolute (so-called "perfect") pitch as my research project. But my department chair was a miserable, tone-deaf grinch who said it wasn't worth the effort. It's amazing that some animals do have excellent pitch - e.g. the hermit thrush tweets a pentatonic scale (the black keys on a piano), but the canyon wren warbles all 12 semitones in the diatonic scale (all the keys). If there were support for it, researchers into avian audition could probably learn a lot about the audible effects of jitter etc from animal behavior in response.

 

D

[jabbr]

I picked A1 knowing that I was in minority -- and as I posted, ascribed it to my being an inexperienced flute and harpsichord listener. As I posted there were several high notes in A2 that I found shrill FWIW

 

At the time I was considering that jitter might soften the music (because I thought likely I picked the "wrong" choice) but now considering that absense of jitter might be softer.

 

I felt "blinded" listening, and not knowing others votes would reduce expectation bias more I think. Very nicely done.

[firedog]

Quote Originally Posted by Sal1950 View Post

Read Lie #4

The Ten Biggest Lies in Audio - ecoustics.com

 

Except the author sets up several straw men there: makes claims that aren't what audiophiles claim and then shows the lie to be incorrect. Several other of his points are also incorrect, or at least only partially true.

 

For instance, it's been shown through measurements that digital clocks only stablilize after at least several hours, and possibly even a day or two. So digital equipment does need to warm up and "burn in" before it sounds it's best. Just one of the many omissions, etc in his supposedly expert article.

[firedog]

I've seen a lot of instances where people preferred the sound of jitter or other types of distortion. Yes, it can make music sound fuller or warmer. It doesn't mean audiophiles aren't discerning, it means they don't know the meaning of what they are hearing.

 

I think bluesman is right. When listeners know what the instruments really sound like, they will pick the more jittery track correctly and will prefer the less jittery track. It's one of the reasons I think a good jitter test should use acoustic instruments with strings and percussion instruments. I think those reveal the effects of jitter more clearly.

[jabbr]

@bluesman

 

Recall seeing a study that one of the "P" peaks was present on BAER with subject having perfect pitch

[Ipoci]

... My initial descriptions are still accurate. The flute simply sounds more like a real flute - the tone is better balanced, the attack is cleaner, and there seems to be less harmonic content. On A2, the flute is a bit fuller and rounder as though it got a 2 or 3 db EQ boost from about 200 to 600 Hz. The breathy attacks are less well defined, and it sounds a bit more like a sampled flute than a live one.

 

The sound of the harpsichord is more natural as well. The midrange harmonics are smoother (which suggests to me that there's less odd order harmonic neo-content or distortion). Again, it sounds more like a real harpsichord than A2, which sounds a bit like a very good electronic keyboard's harpsichord voice. The pluck of each note is also a bit cleaner and clearer on A1.

...

 

David

 

Thanks David, you just described because I had to choose A1 instead of A2 in a clean and simple manner ... At the same time I understood why I chose A2 instead of A1 ... My knowledge of real flute and harpsichord is really bad and I definitely need to improve it. I chose the one that present the flute fuller and rounder. As mentioned by someone on thread ... I'm face down ... :-)

 

Have a nice day. Massimiliano

[bluesman]

@bluesman

 

Recall seeing a study that one of the "P" peaks was present on BAER with subject having perfect pitch

I'm a board certified otolaryngologist, but my sole focus has been on facial plastic surgery so I never treated ear disease after residency. But as I recall, BAER (brainstem auditory evoked responses, for those unfamiliar with the test) has 7 numbered wave peaks of which 1 through 5 are used - I'm not familiar with a "P peak".

[sandyk]

I think bluesman is right. When listeners know what the instruments really sound like, they will pick the more jittery track correctly and will prefer the less jittery track. It's one of the reasons I think a good jitter test should use acoustic instruments with strings and percussion instruments. I think those reveal the effects of jitter more clearly.

 

A lack of familiarity with the type of music supplied isn't too helpful . I also find percussion instruments in particular, as being more helpful in this kind of test. I didn't post my incorrect findings, (although I voted as requested) as I had a lack of confidence in what I was hearing, due to a medical event, possibly a T.I.A. (Transient Ischemic Attack) several days earlier which affected my balance severely. ( Walking into walls!)

[jabbr]

I'm a board certified otolaryngologist, but my sole focus has been on facial plastic surgery so I never treated ear disease after residency. But as I recall, BAER (brainstem auditory evoked responses, for those unfamiliar with the test) has 7 numbered wave peaks of which 1 through 5 are used - I'm not familiar with a "P peak".

 

http://www.ncbi.nlm.nih.gov/m/pubmed/12843255/

 

"P" for positive peaks and "N" for negative ... in some cases they are numbered in sequence and in others by the millisecond time at which they appear.

[bluesman]

Enhancement of neuroplastic P2 and N1c auditory evoked potentials in musicians. - PubMed - NCBI

 

"P" for positive peaks and "N" for negative ... in some cases they are numbered in sequence and in others by the millisecond time at which they appear.

 

Those are cortical evoked potentials, not brainstem evoked potentials. You've confused two separate tests.