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If jitter is a known factor in a digital signal and HDMI transmits a digital signal what is there to make it immune from jitter? Or, are you saying jitter hasn't been proven at all?
"greenie" is a nickname given to rep points..
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Originally Posted by Mr Peabody
If jitter is a known factor in a digital signal and HDMI transmits a digital signal what is there to make it immune from jitter? Or, are you saying jitter hasn't been proven at all?
"greenie" is a nickname given to rep points..
Greenie is something I am immune to.
"jitter" sounds a lot like the "jitter" turntable types claimed was a problem for CD.
Probably will be able to measure it but not be able to tell its coming outta your player.
Doubt if it will be a major fator.:1:
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Quote:
Originally Posted by Mr Peabody
If jitter is a known factor in a digital signal and HDMI transmits a digital signal what is there to make it immune from jitter? Or, are you saying jitter hasn't been proven at all?
"greenie" is a nickname given to rep points..
Jitter is a known factor using certain input/output interfaces(SPDIF), but it has never been proven to be a factor with HDMI. As the signal enters the HDMI cable it is encoded with transition minimized differential signaling. That is the original signal(down one wire) plus a inverse signal of the original(on another wire). When they get to the destination interface(the receiver) these signals are compared, and any differences corrected. SPDIF does not work that way, it just transmits the signal through the cable with no protocol for correction of the signal. The red book standard does not require block-accurate addressing, but HDMI TMDS does.
If jitter was really a big problem with HDMI somebody would have tested and published such a fact. It is easily measured, and we would have examples all over the net. This has not happened, so I am somewhat suspect of claims of jitter over HDMI. We have seen examples of jitter on SPDIF connection everywhere. White papers have been published, examples visually shown, and the effects can be heard which is why re-clocking protocols are usually incorporated in external better quality DAC.
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Comments I saw
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Originally Posted by Sir Terrence the Terrible
Jitter is a known factor using certain input/output interfaces(SPDIF), but it has never been proven to be a factor with HDMI. As the signal enters the HDMI cable it is encoded with transition minimized differential signaling. That is the original signal(down one wire) plus a inverse signal of the original(on another wire). When they get to the destination interface(the receiver) these signals are compared, and any differences corrected. SPDIF does not work that way, it just transmits the signal through the cable with no protocol for correction of the signal. The red book standard does not require block-accurate addressing, but HDMI TMDS does.
If jitter was really a big problem with HDMI somebody would have tested and published such a fact. It is easily measured, and we would have examples all over the net. This has not happened, so I am somewhat suspect of claims of jitter over HDMI. We have seen examples of jitter on SPDIF connection everywhere. White papers have been published, examples visually shown, and the effects can be heard which is why re-clocking protocols are usually incorporated in external better quality DAC.
I don't pretend to understand any of it, but HERE were some comments made by Charles Hansen of Ayre on the subject of HDMI.
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Originally Posted by Feanor
I don't pretend to understand any of it, but HERE were some comments made by Charles Hansen of Ayre on the subject of HDMI.
Notice how he states the way the system works is stupid, but did not say it introduced jitter?
His comments were referring to the earliest submission of HDMI, the 1.1 standard. The 1.3a standard by which most of us are using now uses bit checking processes that correct for dropped bits, and the sync'ing feature(a word clock) reclocks the audio even within this imperfect standard.
Once again, if jitter was an issue in HDMI audio, there would be visual evidence and white papers on the subject all over the net. The system is not perfect, but it does well in transferring information accurately from one place to another.
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It's interesting too that PS Audio recommends an HDMI connection between their new PWT transport and PWD dac (of course, they have a whole new collection of special overly-expensive HDMI cables for sale that claim dramatic improvements over regular HDMI cables as well).
Regarding Marantz, I was referring to something a little less expensive than the one they've announced at $6K, hence my reference to vaporware, since no product announcements have been made. But I really do hope they come out with a mid-priced universal player, maybe in the $1000 range to add some competition to that market. Marantz has made some very decent BR players with small Marantz-unique features that typically give their players a leg up on the competition. They also have a lot of well regarded experience with CD and SACD (albeit mostly 2-channel), and I imagine they could produce a player that is both complete on features and will also sound good.
Speaking of jitter, this page is very informative and has nice colorful graphics:
http://www.tnt-audio.com/clinica/jitter1_e.html
I don't doubt the measurability & pictoral representation of jitter, but what about audibility? Frankly, I'm still a bit puzzled about what it actually does sound like. I've wondered about this for a while, but from what I can figure out, jitter is a lack of clarity, almost as if the sound was coming at me twice in a very short span of time so that each note sounds smeared. Kind of like looking at a screen who's moire is not properly adjusted. But there are a lot of different descriptions of what jitter really sounds like and semantics get in the way. Does anyone maybe know of a sound file on a website that we could listen to to hear what jitter sounds like?
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Originally Posted by nightflier
Speaking of jitter, this page is very informative and has nice colorful graphics:
http://www.tnt-audio.com/clinica/jitter1_e.html
I don't doubt the measurability & pictoral representation of jitter, but what about audibility? Frankly, I'm still a bit puzzled about what it actually does sound like. I've wondered about this for a while, but from what I can figure out, jitter is a lack of clarity, almost as if the sound was coming at me twice in a very short span of time so that each note sounds smeared. Kind of like looking at a screen who's moire is not properly adjusted. But there are a lot of different descriptions of what jitter really sounds like and semantics get in the way. Does anyone maybe know of a sound file on a website that we could listen to to hear what jitter sounds like?
I am sure you can find a sample of jitter online somewhere, but you have probably heard it and didn't know it. Jitter makes digital sound hard and antiseptic. Imaging becomes unfocused, and timbres of certain instruments are lost. Brass sounds hard and screechy, as do some string instruments. If you have any early digital recordings on CD, jitter was pretty prominent on them. Early digital recorders had problems with jitter, which is why external DAC's were much more popular in digital recording studios long before they were available to the public.
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Quote:
Originally Posted by Sir Terrence the Terrible
Notice how he states the way the system works is stupid, but did not say it introduced jitter?
His comments were referring to the earliest submission of HDMI, the 1.1 standard. The 1.3a standard by which most of us are using now uses bit checking processes that correct for dropped bits, and the sync'ing feature(a word clock) reclocks the audio even within this imperfect standard.
Once again, if jitter was an issue in HDMI audio, there would be visual evidence and white papers on the subject all over the net. The system is not perfect, but it does well in transferring information accurately from one place to another.
So ... with reference to your other recent post, does it matter whether the audio standard sent over the HDMI is PCM or DTS-HD as pertains to the jitter problem?
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Originally Posted by Feanor
So ... with reference to your other recent post, does it matter whether the audio standard sent over the HDMI is PCM or DTS-HD as pertains to the jitter problem?
Until somebody offers up an current example of PCM with jitter coming through the HDMI connection, I would have to say no it does not matter.
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Quote:
Originally Posted by Sir Terrence the Terrible
Notice how he states the way the system works is stupid, but did not say it introduced jitter?
He also mentioned that the audio is clocked indirectly via the video signal. Which would seem to work fine for video based mediums, but wouldn't be relevant to audio only formats for which there is no video.
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Originally Posted by E-Stat
He also mentioned that the audio is clocked indirectly via the video signal. Which would seem to work fine for video based mediums, but wouldn't be relevant to audio only formats for which there is no video.
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That is only if PCM audio is used, and there is video stream accompanying the audio. Neither seems to be the case. The audio only titles I have reviewed do not have a video signal present, so the clock is dedicated to the audio only in this case. Secondly, there are far more audio only titles that utilize Dts-HD Master audio than PCM. Dts HD MA is not subject to jitter because the audio is streamed in bit corrected meta-data packets as opposed to a straight bitstream. Once again, he was referring to the 1.1 HDMI standard, not the 1.3a standard.
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Quote:
Originally Posted by Sir Terrence the Terrible
That is only if PCM audio is used, and there is video stream accompanying the audio. Neither seems to be the case.
So, how many Blu Ray audio titles are available today?
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Originally Posted by Sir Terrence the Terrible
Secondly, there are far more audio only titles that utilize Dts-HD Master audio than PCM.
Gee, that's news to me. Where do you buy non-CDs for major music titles?
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Originally Posted by E-Stat
So, how many Blu Ray audio titles are available today?
Not sure of the total, but I have reviewed about 35 between Blu-ray.com and a couple of music mags aimed at the sold in Europe.. My last discussion with Alexander of Surround Records he told me they are going to get VERY aggressive with new releases heading towards Christmas.
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Gee, that's news to me. Where do you buy non-CDs for major music titles?
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Amazon. Search 2L and Surround Records. I am not sure they have all releases from these two companies, but they certainly have quite a few. These labels are classical music only, but discussions with Sony/BMG, Warner music, and Universal Music tells me they will begin releasing Blu-ray audio titles(with video though) next year.
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Quote:
Originally Posted by Sir Terrence the Terrible
Not sure of the total, but I have reviewed about 35 between Blu-ray.com and a couple of music mags aimed at the sold in Europe.
Thirty-five total. Wow!!
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Originally Posted by Sir Terrence the Terrible
...but discussions with Sony/BMG, Warner music, and Universal Music tells me they will begin releasing Blu-ray audio titles(with video though) next year.
With video. No problem. That only rules out 99.9% of all the music available today.
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NF, that link was a great find. That explains a lot.
This has developed into a good discussion
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Still would love to find an actual sound file of jitter. I've searched quite a few sites since yesterday and came up empty.
Interestingly, there's a lot of debate about jitter's audibility. Of course, many of the people who say that jitter is audible are from "the industry." Furthermore, the definition of what it actually sounds like is all over the map. So at the risk of being lambasted about this, I'll ask the white elephant question again:
What does jitter sound like to you?
...And if someone has a spare minute, upload a recording of a jittered file, because the more I read about it, the more confusing this is becoming.
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Originally Posted by nightflier
Still would love to find an actual sound file of jitter. I've searched quite a few sites since yesterday and came up empty.
Files with jitter are really hard to find online. It a demo best done in person, and in a controlled environment. A computer has many areas of contamination that can make demonstrating it pretty difficult, such as a jittery sound card and drive noise.
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Interestingly, there's a lot of debate about jitter's audibility. Of course, many of the people who say that jitter is audible are from "the industry." Furthermore, the definition of what it actually sounds like is all over the map. So at the risk of being lambasted about this, I'll ask the white elephant question again:
What does jitter sound like to you?
The people who work in the "industry" have better access to environments that make jitter easier to hear. (i.e. a quiet studio acoustically controlled with very good electronics). They can directly compare a signal with jitter, and without it in some cases in real time. The definition is not really all over the map, the link you provided did an excellent job of telling what it sounds like. Some folks are just not good at communicating what they hear, but they still can hear it. My description basically matches how the link you provided describes it.
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...And if someone has a spare minute, upload a recording of a jittered file, because the more I read about it, the more confusing this is becoming.
I think you are confused because you have a limited understanding of digital audio as a whole. The more you understand PCM audio, the easier it is to understand jitter. It also makes it easier for you to know what to listen for when jitter is present in the signal. Even if I presented you with a jittery file, you may not be able to hear it because you do not know what to listen for, or may not have the acoustical environment to flesh it out.
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Not exactly the most tactful way to put it, but thanks for the info.
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Originally Posted by nightflier
Not exactly the most tactful way to put it, but thanks for the info.
Sometimes you cannot always be tactful on things that are factual. You should know by now that I am not a sugar coater, I call it like I see it.
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I tried to be cordial and polite....
Calling it like it is? How exactly is this exemplary of that:
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Originally Posted by Sir Terrence the Terrible
I think you are confused... you have a limited understanding of digital audio as a whole. ...Even if I presented you with a jittery file, you may not be able to hear it because you do not know what to listen for, or may not have the acoustical environment to flesh it out.
You don't know anything about me, about my environment, or my setup, so your statement is neither factual or "like it is."
But let's remain civil and let's call your bluff, then: if you're so smart, and you have all this fancy equipment, and a solid understanding of jitter backed by years of experience in the industry, compared to the rest of us peons, why don't you upload a file with jitter for us? And just so you don't weasel out of this one again, why don't we presume that I have a friggin flawless sound card in my computer, too?
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[QUOTE=nightflier]Calling it like it is? How exactly is this exemplary of that:
You have a limited understanding of PCM audio, you have never mixed or recorded in it, and definitely have never studied it. It is obvious, and you need to admit this. To those who understand PCM audio, jitter is not confusing. They know what to listen for. and can create a file with it, or without it. These are indisputable facts.
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You don't know anything about me, about my environment, or my setup, so your statement is neither factual or "like it is."
I don't care to know anything about you, but I do know you don't live in a studio, and do not know much about audio in general, certainly not much about marketing or market trends, or which audio codecs and enhancements are relevant in the future. Remember I have 10 pages of debate, and multiple threads of topics that support my notions. You have not exactly hidden your lack of knowledge on so many audio issues, but let's not dwell on these details.
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But let's remain civil and let's call your bluff, then: if you're so smart, and you have all this fancy equipment, and a solid understanding of jitter backed by years of experience in the industry, compared to the rest of us peons, why don't you upload a file with jitter for us? And just so you don't weasel out of this one again, why don't we presume that I have a friggin flawless sound card in my computer, too?
NF, you must know by now I am not moved by these kinds of kiddy games or inflammatory challenges designed to discredit me. I am not your teacher nor your slave. This is your journey and it's your responsibilty to take it, not for me to make it easy and just give to you. If you want something, get it. Only a child needs to have things handed to them in this fashion. If you want it, go find it yourself.
I don't presume or weasle out of anything. Years in the industry or not, it is not my job or desire to play run and fetch with anyone, especially not you. I play run and fetch with my dogs, not people. You want to call a bluff get a phone, but I do not play that. I hope we are clear about this and do not have to play these games in the future.
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So you are weaseling out of it?
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Originally Posted by nightflier
So you are weaseling out of it?
NF and SirT at it again: shoot me now. :rolleyes:
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Originally Posted by nightflier
So you are weaseling out of it?
I am not your slave dude. I am not responsible for your audio education, you are. Only a weasle and a lazy person depends on others for things they can do themselves. My suggestion to you is get those flipper like things you call hands on the keyboard and mouse and start searching the internet for what you desire. If you are waiting for me to do it, hold your breath until I move....please.
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So again, you're full of opinions in the dugout but when someone calls you to the plate, you're hiding in the locker room. Figures. And this isn't just for me - from what I've read, there's plenty of others who are wondering what jitter really sounds like.
So why not put your pedantic know-it-all hat on and show us what jitter sounds like. After all, you have the gear, right? You certainly believe you have the knowledge, right? You know how to upload files, right? It's not like you don't have the time, because you've spent enough time trolling around behind my posts of late. So what's the hold-up? Is it maybe that you won't be able to prove that jitter is audible? See that's what I'm thinking. So yes, you are trying to weasel out of it because you can't actually do it.
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