What does jitter sound like?

[franepici]

Use your ears, Luke!

 

[Alex McF]

Coops,

 

Please clarify your position. Why is there a link to www.puriteaudio.co.uk and why is there image on your post of a speaker for sale there?

Ashley's position is very clearly stated on all his posts.

More than one 'salesman nothing more who is trying to sell his product' around here?

Personally I welcome contributions from all interested parties, as long as their position is made clear.

 

Finally, I am not sure if Ashley 'has been banned from every UK hi-Fi forum'. But that is coming close to being a badge of honour in my eyes!

 

Over to you.

 

Alex

 

[BobH]

So, at what point does jitter stop being a problem and start becoming nonsense?

 

If, as Ashley has suggested, the problem of jitter has now been addressed by the chip designers - and we no longer need to worry about it - it must be a problem that needs to be addressed. Is the cut-off between good science, and jibber-jabber, price related? Is it the point at which someone produces a product that offers an alternative approach? Is it additional circuitry inside a dac? Or a 'black-box' outside a dac?

 

If there is a problem that needs to be addressed, why would the assumption be made that the chip designers are the only ones who need to fix it, or indeed that someone else can't do it better? To borrow Ashley's car theme, I can get from here to there in a Ford just as easily as in a Ferrari, if I could afford it I would buy the Ferrari - as would most people I suspect.

 

If the objection to jitter solutions is price based then it is not valid in the context of a discussion about whether or not it exists, or can be heard. If the objection is science based, then why are chip designers fixing it? If the objection is based on its non-audibility then, equally, why are the chip designers fixing it? AFAIK jitter exists and is addressed in a number of ways by both chip designers and audio equipment manufacturers - it would be a massive leap of faith to say that all these solutions are equal and I need not to concern myself with them. Whether or not I can afford the best possible solution is a different question.

 

[Purite Audio]

Alex Hi, yes I am a saleman, I run a small audio business in the UK. I take great pains to try and listen to everything I possibly can, form my own opinion and then if i can put my' money where my mouth 'is and stock that product. I respect Daniel's ( Weiss ) products and asked to represent them, I have listened to some 40 different dacs and cdps now, Mike Stahl's and Daniel Weiss' stood out for me.

I believe I have made my status quite clear, as has Steve at Empirical , whilst supporting my own choices I don't feel it necessary to 'rubbish' others. Very Best Keith.

 

 

[Ashley James]

Bob

Parts prices are peanuts and cost isn't really a consideration. All the bits to make a jitter free stand alone DAC probably amount to less than £30-£40 for a specialist manufacturer and much less for a volume one like M-Audio, Edirol, EMU, RME or Apple. I've excluded the casework that varies according to hiendidness.

 

I'm told there is a good and sensible review in Hi Fi Choice comparing a variety of DACs using a Cambridge Audio Amp, which is good because it's powerful enough and designed by a recognised authority, Doug Self and a pair of our now discontinued Neutron IVs. The most expensive was marked down because it was ten times the price of the cheapest and not significantly better. In my opinion this is a very fair assessment. As far as jitter is concerned, it is one of several factors that contribute to a greater or lesser extent to the overall sound quality. It cannot be heard in isolation.

 

I make no bones about my company or my desire to sell my products, however I really enjoy this Forum and the people on it and most of all I care passionately about audio and the future of the industry. Therefore I've spoken to Chris about my wish not to fall foul of what he considers reasonable and I try to talk in general terms as much as I can. In my opinion all manufacturers contributions are valuable and all Forum members are capable of recognising cynical sales ploys when they see them. They probably are still able to discern useful information from them too.

 

The rules on this Forum do not prohibit promotion but the UK ones do, which makes it very difficult for a manufacturer to either defend or explain, especially when there are factions, in some instances encouraged by manufacturers, who'd like to silence what they don't want to hear. However, despite this, a particularly vindictive series of attacks, both on forum and behind the scenes, my "robust" defence earned me a week's cooling off period. The moderator then told the aggressors that he felt he'd been wrong to do it and that he'd bowed to pressure. He also said that new ideas had ruffled some feathers and that might be good.

 

In the circumstances I really appreciate the kind words of support that some of you have given me and I promise I will try not to be too much of a salesman.

 

Ash

 

[cfmsp]

 

 

Ashley,

 

Thanks for your response in explanation of your position.

 

We have much about which to 'agree to disagree', which is perfectly normal.

 

The intent of my post above was to point out why I thought your opinions here do not seem to garner the full weight/impact that you (seem to) desire. Apparently, in so doing, I've gotten under the thin skin of at least one poster here - a 'supporter' apparently. If my comments seemed rude to you - my apologies to you and you alone - but I rather doubt that this was the case.

 

There was an interesting short article in Stereophile magazine this month which referred to two styles of audiophiles - Levelers and Sharpeners, the most salient characteristics were that latter of which maximizes the differences between components, while the former minimizes the differences between components.

 

an interesting read. I couldn't find the link yet, it's only just arrived by post.

 

cheers,

clay

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[BobH]

Hi Ash,

 

Sorry, but you've taken the one issue I mentioned as not being relevant to a discussion on the subject of jitter, and created a response to my observations around it! Your post does not address the points I considered to be more relevant - it simply, once again, re-enforces your stance that jitter is a non-issue for the end-user. Whilst this position may well be valid for your chosen audio requirements, I disagree that it will be equally valid for all solutions.

 

If it was not a problem, chip designers would not have addressed it. If someone else maintains that they have a superior solution to it, then I do not see why they automatically become 'snake-oil' merchants because their products are sold for a premium. To dismiss an audio solution on the basis of price is, IMHO, completely irrelevant to all discussions of a technical nature.

 

In the context of the original question, (what does jitter sound like?), then 'don't worry about it - you won't be able to hear it' is a valid response. As, also, are the responses from those posters who have put a great deal of time and effort into trying to find a better solution than the one offered by chip designers.

 

If you're seen as encouraging forum readers not to investigate ways in which their systems and/or knowledge can be enhanced then you must expect a certain amount of 'FLAC'.

 

For any forum member who is keen to read up on the subject, then the google trick of specifying a filetype may well reap rewards. Without the quotes : "jitter filetype:pdf" will yield a couple of dozen well researched papers on the subject, both for and against. What did I learn from doing this search? When the time is right for me I will be auditioning products along the lines of those provided by EmpiricalAudio and others.

 

Rule out nothing.

 

[sastusbulbas]

From what I can gather, from the attitude and evidence gleamed here, that all this Music server, best source for digital is all baloney. You are stating that a £3k mac with a £700 soundcard feeding a DCS Scarlatti s not really that much better than a £280 laptop from PC world feeding a Cambridge Audio Dacmagic? Well what else can be deduced from its all the same type comment?

 

Even though the Scarlatti offers lower jitter, distortion, noise floor and low level resolution, most of the measured differences are within the 4th decimal place below 0.001 in comparison to the Dacmagic. So if you are using standard CD rips, and live in the average UK home any audible difference would have to be imagined.

 

We have no measurement proving the reference server or £3k G5 with a £700 soundcard is any more capable of providing a measured audible improvement over bit perfect data from a £280 basic laptop, after all digital out is digital out, it's all 0's and 1's, and bit perfect is bit perfect!

 

No wonder many tend not to waste time and money on such, and even without trying conclude that computers and audio are rubbish. I am glad my own ears tell me what I hear and prefer, as it is clear all you get is biased opinion and argument even if as in my case you want to improve your computer as a source.

 

Personally I think something has went wrong in audio, if all a DAC has to do is measure well and make ALL sources sound mediocre to be classed as a reference. The truth is in my opinion a shit digital source is a shit digital source no matter how much you spend on a digital band aid DAC. No wonder Hi fidelity has died a death, and it has all became so mediocre and costly. I remember days when audible differences were approached with vigour and interest, not just bashed and the user abused and belittled through ignorance.

 

The truth is, it says a lot about the mediocrity of many of the users systems and music, not to mention the reasoning. Many of you are happy with your systems, those that want to do better or hear different, or have old or different systems, or are looking for an alternative approach are looked at as if they got off the wrong bus in the wrong town.

 

Steve

 

[tfarney]

"So it is a load of rubbish! many of you are saying if a digital output has a high level of correlated jitter removing this cannot be audibly beneficial, it cannot be heard. It is nothing to worry about and need not be addressed?"

 

No, what we're saying, and what all the measurable evidence seems to indicate so far, is that if you have a DAC of reasonable quality and contemporary design, that the level of jitter being generated is not high enough to be audible, therefore, removing it will not be audibly beneficial.

 

Now, in a studio environment, and it's important to note that this is an educated guess, I suppose further reduction of jitter may be important because jitter, like all noise in recording would tend to multiply with the multiple stages of recording and production. At home, you're converting a digital signal to an analog one once. The jitter generated by modern DACs in that conversion appears to be below the level of audibility. I don't hear it. I think I'll worry about other areas of my signal chain. You can, of course, worry over it if you like. That is, however, different from calling jitter rubbish or believing it does not exist.

 

Steve -- I'm still here because there is much more to discuss related to computer audio than jitter and the audibility of computers shuffling zeros and ones. And because it is a pretty cool audiophile community where there seems to be room for pragmatists and tweakers to live together in relative peace.

 

Tim

 

 

[LAMF]

I concur with you Tim.

There is much more to discuss here. Let's move on.

 

[DavidJPettifor]

tfarney wrote:

No, what we're saying, and what all the measurable evidence seems to indicate so far, is that if you have a DAC of reasonable quality and contemporary design, that the level of jitter being generated is not high enough to be audible, therefore, removing it will not be audibly beneficial.

 

Definitive answer and move on? I think so.

 

--

djp

 

[Tog]

I find the discussions interesting, the sniping pointless and the goal of listening to high fidelity music a worthy one. If along the way some of us feel that jitter is a relatively minor blemish in the digital domain then there is nothing unreasonable in that view. I think that there are already some very good solutions and have a dac with a well regarded re-clocking mechanism so I don't worry about it. I do think that the quality of recording has far more of an impact in most cases and would be interested in the argument of anyone whoever they are who disagrees.

 

I don't feel confident enough to trust that because people give us expensive solutions ..ergo there must be a problem. Cause and effect doesn't always work properly in the audiophile world. Whilst I'm at it I don't believe in Father Christmas, hedge funds or tube amps but thats my problem.

 

yours far too seriously, tog

 

[audioengr]

Ashley - I'm still waiting for answers to my questions.

 

Steve N.

Empirical Audio

 

[brimac]

It's interesting that this discussion around jitter draws such passionate postings. There's such a clear dividing line between both camps; both equally adamant supporting what they believe.

Computer audio has the potential to bring our systems to the next level; it's common consensus that hi res is a workable model that has legs, unlike SACD or DVD A. it's technology that will be implemented across a broad customer base; your neighbor may not know anything about jitter but he may buy a Logitech Duet.

Computer audio exposes high end excesses like 30k CD transports and casts doubt on the high end's credibility for many. If bits are bits and a $500 computer gets those bits to the DAC, people question whether extreme products like the aforesaid transport ever represented value. And so we have our suspicions that jitter audibility is just another creation of this industry to hose fear and sell product. Perhaps computer audio can save the high end, but i don't think so. The high end stopped being broadly relevant a long time ago. It's actually a laughingstock and held up to derision in the mainstream press, and among average music listeners. Something tells my this discussion about jitter only contributes to that perception.

And then we have computer audio. It represents value in spades to audiophiles. we've switched out our insanely expensive cd players and, at least in my case, have improved on them sonically, not to mention all the other benefits that are part of the package. So what does the high end industry do in the face of the trend towards file-based music delivery systems? Well, music servers like Sooloos and Blue Smoke. Wow, there goes more credibility. Many thousands of dollars more than a computer, with less flexibility and questionable advantages. They just don't seem to get it, the high end. And now the high end is talking to us about jitter. You know what, i just don't buy it. I like Ashley's approach; maybe people that think like that are the messiahs to take us out of the barren wastelands of the high end and deliver us to the promised land. 'Cause let's face it, the current priests of the high end are lost and preaching the same old story. You just need to look at all the very expensive CD players introduced at CES to understand that they just don't get it.

On a separate note. The people here who are concerned about jitter are becoming increasingly rude and are resorting to personal attacks upon those who aren't really too worried about jitter. Perhaps they feel threatened, i don't really know. i do know that Tim and Tog and Ash articulate their perspectives cleverly and raise the tone of the discussion while staying well-mannered and interesting. Comments casting aspersions on their motives, reasoning, hearing, or the resolving nature of their music systems seem to be an attempt to discredit their beliefs by discrediting them personally. Who knew Carl Rove was an audiophile?

 

[Ashley James]

Thousands of radio stations, On demand TV programs without adverts that you can watch when you feel like it, Movie purchase, streams or rentals, slide shows of your photographs, being able to talk to and see friends all over the world whilst listening to you music, surfing the net and even watching every episode of the original Buck Rogers Movies. The possibilities may not be endless yet, but they are getting there and it's very exciting. I think everyone should be considering all of the possible uses for a decent and integrated Media computer rather than carrying over audiophile worries and building up a system that either precludes or makes dovetailing with all other functions difficult in the name of audio perfection. We've been heavily into this for two years and had a chance to see how people's systems evolve and how many rue the day that they FLAC'd terrabytes of their CDs!

 

Many have more than one system now, some stream video as well as music, lots have taken up photography and quite a few will admit they are glad to be rid of the obsessions involved maintaining and upgrading legacy separates.

 

Tog's attitude to jitter is the norm and most people, after a bit of angst, switch to iTunes and love it and so on. Most don't want desktop computers anywhere visible, so they stream and use digital outputs from AE or Sonos or PS3 and most even discover that the iTunes music downloads are very good because they are, as has been discussed on this excellent Forum.

 

This thread has been worthwhile if it has re-assured people that they don't need to worry, but we should move on and broaden our horizons in my view. Let's face it, there's a pretty big exodus from hi fi and this obsessing has to be a factor.

 

Ash

 

 

 

[Purite Audio]

This has been posted before but seems pertinent,

http://www.enjoythemusic.com/magazine/manufacture/1208/

 

[Tog]

Glad to see a sense of humour returning to this thread.

 

Actually there are some similarities between those who obsess about which tubes to "roll" - Stalingrad era "Comrade" SP452 or Westinghouse "Eisenhower" SP5664 ...."yes a much richer midrange but its burnt a hole in my floor"..and those who fret about jitter levels.

 

No I apologize the tube rolling sounds like fun!

 

Tube amps have the added benefit of looking cool and providing central heating.

 

Jitter just provides me with amusement.

 

Yours more happily, tog

 

[The Computer Audiophile]

Hi Guys - It's pretty cool that most of you are willing to breakout your senses of humor after a long passionate discussion such as this one. This isn't brain surgery and nobody is going to die based on our beliefs about jitter, unless they get worked up over the discussion and have a heart attack. I'm happy everyone has dropped their metaphorical scalpels and can now turn up their stereo.

 

 

 

 

[davidR]

Steve, when you list your specs at 2 pico seconds is that for intrinsic or accumulated jitter? Either way that is quite impressive.

 

[Tog]

Oh no.... davidR now you given a name to it as well ....

 

"Accumulated jitter" should I be afraid? and what happens if my DacX can only try for 4 pico seconds...how will I show my face in public?

 

Sleep will not come easily tonight

 

yours sleepless, tog

 

[Ashley James]

If I go out and buy an expensive hi end DAC and then discover that it has more jitter, what I need to know is whether or not it will be better quality and therefore more musically involving?

 

Ash

 

 

 

[shenzi]

only bothers me if it causes the wine to spill over the edge of the glass.

 

[davidR]

Keep throwing out the jokes please, hehe. I won't be offended, I already know I'm a nut. Can't take myself that seriously. This hobby is more interesting and enjoyable when doubting Thomases exist in my opinion. I guess Bob Katz and Dan Lavry are complete morons wasting there time with discussions on jitter? Of course. Everyone comfortably believes we know everything these days, oh cmon. ;] The science community as a whole also thought the world was flat for some time. Thank God for people like Magellan who had a sense of adventure and thought outside the sphere. Disagreement makes things more interesting. I enjoy this site.

 

[shenzi]

Even the Greeks knew the earth wasn't flat. I'm not sure the same can be said for one or two non-computer audio companies.

 

[sastusbulbas]

I too am glad to see it's not being too serious in here, a bit of humour is welcome.

 

If I get round to putting another computer together for audio using better components I will report back on how much a difference removing the jitter via the Genesis DL makes, this computer is at some point going into the spare room with a bit more HD space and such, IF a sound card improves matters, though a Dacmagic with USB may be a better choice? (I want a reasonable cheap jukebox here) Of course my poor Mobo is not great with direct spdif out, but I am sure I have read that the AC97 chip is a poor choice.

 

I guess those without modern Dacs will just have to suffer, clearly it is too much to expect most digital source manufacturers to put an effort into manufacture these days, but what can we expect when manufacturers take components worth pennies from shelves and do the plug and play manufacture.

 

I would still like to use a well constructed source capable of not relying on a mediocre "make it all the same" dac and faith. Luckily my system allows me to hear the effects of a poorly implemented digital source, no doubt I will have even further upgrades to enjoy before age and deafness have me suffering dementia and thinking all the manufacturers are making it up and it all sounds the same!

 

(To be taken with a touch of humour guys!)