[Daygloworange]

Can jitter really be considered noise or compared to noise?
I guess it depends upon how you define noise.
I think of jitter as skewing the time domain.
I think of noise as extra information that shouldn't be there.
Perhaps the ear is more sensitive to time smear than noise.

If the artifacts or performance gains between whatever medium are far below the level of music, or beneath the noise floor present on the recording, then it's a moot point. It's purely an academic discussion. This is what Ethan keeps referring to.

Noise is embedded in a recording right from the onset. Microphones usually have quite low signal to noise ratios. They have a lot of self noise. Ratios of some ubiquitous microphones can be as low as 67 db signal to noise (signal to noise of microphones is calculated based on the db level of self noise present at a 94db input level).

That is the microphone itself. Then you have (in the case of older recordings) many gain stages, and tons of circuits to run through and recording medium transfers, before it ever hits the final pressing.

The you press play on your CDP or drop the needle on your TT in your listening room with it's own ambient noise floor and room acoustics causing reflections that add distortions and comb filtering.

We sit down, with our mature adult ears, that have a lopped off high frequency response, and advancing tinnitus, and listen for jitter, bit depth and sample rate anomalies of noise laden (see above) recordings.

Coming from a pro audio background, these are the reasons why I don't feel the need to obsess about a lot of these things. You are listening to a recording of mostly music, and quite a bit of noise at the same time.

Cheers

[TheChairGuy]

16/44.1 verses 24/96 files for your listening pleasure:

http://www.soundkeeperrecordings.com/format.htm

Did anybody else download this helpful link?  Both took some time (even on fast Comcast cable internet service) and the 24/96 took a very long time.

I'm playing them on just my laptop...garbage speakers and all. 

Admittedly, the differences were slight, but there they were - would those differences be magnified on a 'real' system?  Maybe.

The difference was something akin to the differences I've heard with non-oversampling and oversampling DAC's (my old MSB was switchable between those choices). It's not quite as pronounced as the differences in CD and DVD-A (recorded and playback) versions of Neil Young's 'Harvest, but along those lines.

The guitar (mandolin?..remember it's being played on my laptop ) lick, especially amongst the solo opening (before the other instruments and voices likely distort the cheapie internal amp and speakers) has very noticeably more body/substance to them.

After that it was a bit harder to discern.

I think that 'body' is called resolution...closer to making instruments/vocals sound like live/real.  Redbook cannot achieve it, DAD 24/96 comes a lot closer to it.  It's not the bits (as already discussed, precious few amps have greater than 100db range to take advantage of the extra bit depth)...it's the sample rate...44,100 is not sufficient to my ears. 

Jitter is a small matter next to that of the larger ones like higher rate sampling, room acoustics and lower distortion amplification and speakers - that's been mostly likely taken care of well enough the past 5 -or-so years. 

I am left wanting for more with nearly any CD I ever listen to. Even this little sample made me want to turn the volume up for more body...except that as you turn it up it becomes more obviously lacking.  I don't know what sampling rate would achieve 'perfection' for me - or you - I merely know 44.1 is insufficient (for me). What we as audiophool are banging up against is the very real limit of Redbook recording technology now and hoping it ain't so 

Most of the general public could not care less - but we obsessed audiophools should expect better and higher resolution than Redbook offers. Fortunately, there are formats that exist that will allow for this....vinyl, reel-to-reel, DVD-A and (likely) Blu-ray.  I'm leaving out SACD as there is something completely amiss with that format - I've read it's phase issues, I don't know, I only know it sounds plain weird to me every time I've heard it.

It shouldn't be too surprising that Sony adopted the 24/192 with MLP rather than force feed their DSD system for audio on Blu-ray...it's just rotten somehow, even at 2.8 million samples per second. 

[darrenyeats]

Yes but can you tell the difference when you don't know which one is being played? That's a different matter.
Darren

[Geardaddy]

We sit down, with our mature adult ears, that have a lopped off high frequency response, and advancing tinnitus, and listen for jitter, bit depth and sample rate anomalies of noise laden (see above) recordings.

DGO, speak for yourself....

[TheChairGuy]

Yes but can you tell the difference when you don't know which one is being played? That's a different matter.
Darren

Yup - it is a different matter.  All that I can compare to are three things:

1.  I have only one disc in both CD and DVD-A (aforementioned Neil Young's 'Harvest').  The difference in sound quality is startling.  As the Redbook mastering was done 20+ years ago and the DVD-A re-mastered for DVD-A less than five...I cannot be sure how much  of the difference is technology and how much is part of the digital learning curve in recording/mastering.

Truly, the (commercial) CD's mastered 20+ years ago were on average worse than those today....this is mostly true.

2.  I squirm in my chair on 80% of the CD's I listen to and only about 50% of the DVD/DVD-A's.  However, several of the DVD/DVD-A's were re-masters from original redbook recordings...so they were kinda' fouled from the beginning.

Most CD's sound anemic, lacking body and have tinny/reed thin treble sounds.  I'm no golden ear - it's pretty simple to hear it if you stop fooling yourself and just leave pre-conceived notions behind.

3.  The best (DAD) recordings I have ever heard are a couple of AIX Records releases...which are purpose-recorded DVD-A's at 24/96 with MLP.  They are so much better than anything else, including vinyl, it's remarkable 

To more fully satisfy myself that it's the technology, and not the mastering as some try to puffer up and excuse Redbook for, I need to go out, buy some more AIX Records DVD-A and/or DVD-A's based on old analog masters.  DVD/DVD-A's based on Redbook masters have already been plagued by mid-fi sonic quality.  However, I am so engrossed in vinyl with good direct drive and Grado cartridge with shibata (most natural sound I know of in vinyldom), that I have little inspiration to, frankly.  I'm happy - enough - now.

All you need is about $200.00 to have an experiment for yourself.  Buy an Oppo player and maybe 3 DVD-A's from original analog masters (there is plenty out there pre-1980).  That's it, you're hooked - and will realize as it is a DAD it should be plagued by the same issue of jitter as CD (on the same machine, in particular).....but you won't care as it's the format, and not at all jitter

Worrying about jitter with a mid-fi recording and playback technology is a time-wastin' exercise.  There are truly better recording technologies out there, old and new, it is just a matter of giving up some form of convenience in adopting them.  You can't plop your R-to-R, vinyl disc, or DVD-A into your automobile, load them into your i-pod or hard drive without using up a lot of memory, but they are all sonically superior to Redbook.

I am only hoping that Blu-ray becomes the de facto audio and video standard that allows us to all listen and watch to higher standards without giving up all the convenience in the future 

John

[darrenyeats]

John,
Before I get going let me say I accept your experiences totally. What I want to do is question the conclusions you arrive at from these experiences. Maybe it's you, and not the skeptics, who need to open their mind?

In your point 1 you state you have just one album in CD and DVD-A and acknowledge the mastering is different.

So I can only conclude you are basing your - to be fair - very negative opinions about the CD format itself on how CDs have sounded to you in general. I am guessing these impressions are under normal listening conditions i.e. sighted. If I am wrong on that please correct me.

I agree many CDs are mastered poorly. And I agree that DVD-A, being a very minority format aimed at audiophiles, can sometimes have better mastering. Conspiracy theorists (such as me) suspect there might be sometimes a deliberate difference in mastering. Perhaps that is what you are hearing. But wait...you might be surprised at the stunning difference between different masters on CD. Please have a look here for an example: http://forums.slimdevices.com/showpost.php?p=270134&postcount=25. Please do follow the link and just look at the waveforms. If you'd heard the inferior master on CD, I for one would forgive you for thinking CD is crap!!!! (BTW Jeff Buckley fans, the better master is much much much better to listen to!) Perhaps there is a bit of placebo effect mixed up with the mastering too, since you hate CD with such a passion?

Either way, aren't you jumping to a conclusion about the CD format itself a bit hastily? I believe quality of mastering is more fundamental than anything in the domestic replay chain, and not an excuse at all. Finally, this view on CD versus hi rez is based on well documented blind listening experiments. I have subjective experiences too (different to yours) but I've come to feel they don't prove much. The music industry loves peddling hi-rez formats as audibly better, but I think only because they have more DRM!

I'm not trying to prove you wrong, because I can't prove a negative. But personally I feel you or someone else needs to come up with more convincing evidence or argument.
Darren

[miklorsmith]

Sooo, still no definitive answer on the "noise vs. primary signal" question yet?  This is elemental to Ethan's claims.  However, if there is more to it than noise levels we're right back to jitteradication again.

I don't think redbook is broken at all.  I have a couple of really killer players.  John, you should take a field trip to Seattle.   

[BrianM]

I'm no golden ear - it's pretty simple to hear it if you stop fooling yourself and just leave pre-conceived notions behind.

Gee, John, that's kind of an obnoxious stance, isn't it?  Those who may not agree with you are fooling themselves with preconceived notions?  (As if you couldn't possibly have any yourself?)

To more fully satisfy myself that it's the technology, and not the mastering as some try to puffer up and excuse Redbook for,

No, I didn't notice anybody here making excuses for poor mastering, of any medium.  If you haven't heard redbook CDs that are well-mastered enough to please you, then maybe just chalk it up to different strokes. You won't persuade anyone by telling them they're fooling themselves.

All you need is about $200.00 to have an experiment for yourself.  Buy an Oppo player and maybe 3 DVD-A's from original analog masters (there is plenty out there pre-1980).  That's it, you're hooked - and will realize as it is a DAD it should be plagued by the same issue of jitter as CD (on the same machine, in particular).....but you won't care as it's the format, and not at all jitter

Lots of people have done as much and reached a different conclusion, and a couple have said as much in this thread.  I doubt that starting to repeat yourself is going to get us anywhere at this point.

[TheChairGuy]

Either way, aren't you jumping to a conclusion about the CD format itself a bit hastily? I believe quality of mastering is more fundamental than anything in the domestic replay chain, and not an excuse at all. Finally, this view on CD versus hi rez is based on well documented blind listening experiments. I have subjective experiences too (different to yours) but I've come to feel they don't prove much. The music industry loves peddling hi-rez formats as audibly better, but I think only because they have more DRM!

I'm not trying to prove you wrong, because I can't prove a negative. But personally I feel you or someone else needs to come up with more convincing evidence or argument.

Darren, I'm the definitive word on nearly nothing  .  I, too, am looking for a more conclusive argument than my own.  I'm 44, I've lived with CD since the early-80's.  I worked in a radio station at my high school 1978-1981....it was there we all heard Ry Cooder's album (name forgotten) that might have been the first commercial redbook recording (issued on vinyl as DAD was a couple years away still).

A group of us sat in the back studio when we received it, cued it up on the Technics decks and listened.  We were all bowled over by the relative quietness of the recording......and the horrendous screechy sound quality.  Some of it was mastering, I am certain, but a good bit of it is inadequate technology to do justice to music. 

Surely the recording process, and mastering techniques have improved over the years and CD's sound, generally, better now. But, it's a 2-and-a-half dimension format trying to portray a 3D event.  No screwing around with jitter, or 192K oversampling or pruning and simplifying back to non-OS will change the recording issues inherent in it. I don't know what level of sampling is needed to achieve adequate resolution, but 44.1 doesn't seem quite enough.

Most don't care, but we're snotty audiophools - we should.  It's not worth spending more irrational money on (everybody's idea of that is different, of course) a mid-fi technology.  It's not worth spending time dithering or jittering when the issue is greater than it's parts.  Also, I totally 'get' that it is in the best interests of the corporations to try to get us all to unhook from CD to something else their peddling now 

At least I have finally done something in this topic....I've changed Denny/Daygloworange and Mike/miklorsmith's impression of me as anti-digital / pro-analog to plain ole' anti-Redbook CD 

I would love to replace my noise-plagued, non-linear phono system with something it's equal with more convenience - I tried with CD and failed.  Hundreds of thousands have tried and failed.  I'm not that nostalgic - I love music. It ain't jitter - it's the format   

John

[BrianM]

Sooo, still no definitive answer on the "noise vs. primary signal" question yet?  This is elemental to Ethan's claims.  However, if there is more to it than noise levels we're right back to jitteradication again.

I think DGO made the point well enough:

If the artifacts or performance gains between whatever medium are far below the level of music, or beneath the noise floor present on the recording, then it's a moot point. It's purely an academic discussion.

[Ethan Winer]

If the artifacts or performance gains between whatever medium are far below the level of music, or beneath the noise floor present on the recording, then it's a moot point. It's purely an academic discussion. This is what Ethan keeps referring to.

Yes, this is exactly the point, and I believe I have found a way to prove this to everyone's satisfaction - whether they live near me or not. I'll outline my proposal below, and give the nay-sayers a day or so to confirm they agree my proposal is a fair test.

I will take two recordings - a piano performance and an "industrial music" pop tune I did recently - and add nasty sounding artifacts much softer than the music in random places. It's tough to generate controlled amounts of distortion such as 0.02 percent, and the amount of distortion is generally worse on peaks than softer parts. Since higher order harmonics are more noticeable and more objectionable than lower harmonics, let's skip the harmonics altogether. Instead I'll add a treble-heavy "crunching" sound that is sure to be more objectionable than 7th or 9th harmonics, or even IM distortion and aliasing which are non-harmonic and thus nastier still. I'll create the most obnoxious sound I can, with a heavy emphasis in the 2 to 4 KHz range, and mix that in with the music. But I won't say where the noise is added. It's up to those who believe they can hear ultra-soft artifacts and distortions to identify where I added it.

I'll also add the same noise to a pure 100 Hz sine wave at varying levels as a control. This way everyone can clearly hear the noise I'm adding, and learn what to listen for. This 100 Hz version will also be educational for those who haven't done tests like this because then they'll discover how much of a "needle in the haystack" this really is. When you see how difficult it is to hear the noise 80 dB below a pure 100 Hz sine wave, you'll have a greater appreciation for why I insist it's impossible to hear artifacts that soft when real music is playing.

If there's a general agreement I'll put this together in the next few days, and post CD-quality wave files on my site with links here. Then, if nobody can tell where the nasty noise comes and goes at -80 or -90, we'll have proven that things like jitter and capacitor distortion at -120 must be inaudible.

So what do you all say - sound like a plan?

--Ethan

[miklorsmith]

I think there's more to it than noise levels.  There, I said it.  I can't defend it or quantify it or analyze it or anything else.  If the test subject is noise artifacts Ethan's test is fine but I disagree that's where it ends.

Go ahead, try to argue with that!   

[Bob in St. Louis]

So what do you all say - sound like a plan?

....and the gauntlet is cast.

[JeffB]

I don't think my point as been addressed very well.
I don't think jitter can be compared to noise.  It is not noise, but a smearing of time.

I don't really have an opinion on whether one can hear jitter. 
My system has way too many flaws to even think about jitter yet.
I am also not a signal processing expert.

However, from a layman, it just seems that noise and jitter are completely different things.
They are orthogonal distortions.

Look here. 
http://www.stereophile.com/reference/193jitter/index.html
Scroll down to Image A vs Image B.

[woodsyi]

I don't think my point as been addressed very well.
I don't think jitter can be compared to noise.  It is not noise, but a smearing of time.

I don't really have an opinion on whether one can hear jitter. 
My system has way too many flaws to even think about jitter yet.
I am also not a signal processing expert.

However, from a layman, it just seems that noise and jitter are completely different things.
They are orthogonal distortions.

Look here. 
http://www.stereophile.com/reference/193jitter/index.html
Scroll down to Image A vs Image B.

I heard what I heard.  It was a spatial and coherence issue within my hearing range.  My hearing must be really good or I am delusional.  Either way, I am a happy camper.   

[BrianM]

Hmm, Ethan it seems to me your test would be more apropos if you offered people two recordings of the same track, one with noise consistently throughout (i.e. data correlated jitter) and one that was "clean", then see if people can identify which recording is the noisy one.

[miklorsmith]

How about this wild ass hair - noise is an artifact of bad clock timing and the easiest to measure but maybe isn't the end of the audibility question?

[BrianM]

I don't think my point as been addressed very well.
I don't think jitter can be compared to noise.  It is not noise, but a smearing of time.

I was wondering about this, too, but one thing that occurred to me is simply that it's never actually time we're speaking of, but spacetime, which as everyone knows is "smeared" (bent, warped) by objects with mass.  Since speaker drivers have mass, things are all f-ed up at that point anyway.

Seriously though, if you take a pristine signal and "time smear" it, what you're basically doing (as far as I can figure) is still adding something to the original signal, i.e. the same signal only much softer and out of phase (or something).  something added is by definition noise.  I think this has to be an academic consideration given the minute impact of the change, kind of like if you took a high def photograph and reproduced another one on top of it displaced a couple picometers or whatever.  Would it still look high def?  Probably.  But that's only a guess on my part.

[miklorsmith]

But in a digital stream, what is the "original" signal to offer a basis for comparison?  Can we look at the digital stream without converting it somehow?  Or is it the post-conversion analog stream compared to . . . ?  It's the conversion process itself at issue, right?

[woodsyi]

I lost track of this thread and I don't have time to read all the linked articles.  I think Ethan has a point that additive noise below audible range is negligible.  I also think jitter can negatively impact the existing main signal that can be heard.  It's not a loudness issue, it's a time-spacial issue.  IMHO only.