First let me say hi...I am new here and am having a little issue.
I am new to all of this. I have searched the forum, but cannot find the answer to a couple of questions, specifically the cable question.
I have my dish receiver hooked up via HDMI (for video), however, I originally had a DVI-HDMI with my old cable box and the Dish guys gave me an adapter so I could go HDMI-HDMI from the Dish box to my TV.
My audio is running from the Dish receiver to my Sony receiver via an optical cable.
The problem is this. The audio seems to come through a fraction of a second BEFORE the video.
My question is this. What steps should I try to solve this issue? I have tried changing channels and also it doesn't seem to matter HD or standard channels.
Does having that HDMI/DVI adapter make a difference? Is it slowing the video signal down? Should I get a direct HDMI-HDMI cable and get rid of the adapter? Will the signal process faster, therefore matching my audio?
I have also read about cable quality and length. Both optical and HDMI cables that I have are quality cables and not very long.
Any ideas? BTW-I have not called DishNetwork yet.
Finally one last question a bit off topic. I have seen these optical splitters. Do they work good and without loss of quality? I don't want to actually split the signal, but I have an XBOX that is using an optical audio and I have a DVD that I want to use one as well, but my receiver only has 2 inputs and the Dish is using one.
Here is my set up
Vip 622 DVR box
Samsung LCD LN-T4661F
Sony STR-DE545 (no delay settings)
I hope this makes sense...I am a n00b here. Thanks in advance.
Audio delay / lip-sync error
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akirby
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I doubt the adapter is the cause of the delay, but can't say 100%.
Does the delay happen on all channels, all programs? Sometimes this is caused by the broadcaster or local station equipment.
If your TV has HDMI then it probably also has an optical audio out. You could try connecting the optical audio out from the TV instead of the cable box. That might work.
Does the delay happen on all channels, all programs? Sometimes this is caused by the broadcaster or local station equipment.
If your TV has HDMI then it probably also has an optical audio out. You could try connecting the optical audio out from the TV instead of the cable box. That might work.
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tmoca
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Thanks for the reply.
It seems to happen on all channels, although the Dish is new, so I haven't really watched all of them.
I did try running my optical plug out of my TV into my Stereo Receiver as you stated. Not really sure if it was a whole lot better. But I do know that it did not broadcast properly. My receiver is older, but it supports DTS and Dolby digital. I have a little blue light that lights up when it is detecting the digital signal. When I route it through the TV as you mention, it only recognizes it as PCM.
It seems to happen on all channels, although the Dish is new, so I haven't really watched all of them.
I did try running my optical plug out of my TV into my Stereo Receiver as you stated. Not really sure if it was a whole lot better. But I do know that it did not broadcast properly. My receiver is older, but it supports DTS and Dolby digital. I have a little blue light that lights up when it is detecting the digital signal. When I route it through the TV as you mention, it only recognizes it as PCM.
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Richard
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What you are experiencing is audio delay due to all the video processing that takes place with the new digital TVs. The solution is an audio delay device. Some scalers have this built in like the DVO line. Another recent newbie is http://www.alchemy2.com
Some receivers I hear are providing this too. TV manufacturers have begun putting delays in the product for the internal speakers but that won't help you with external sound products.
Some receivers I hear are providing this too. TV manufacturers have begun putting delays in the product for the internal speakers but that won't help you with external sound products.
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bradtothebone
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I use the Felston unit found here:
http://www.lipfix.com/felstondd540orders.html
The newer DD740 is now available (I have the 540) at a cheaper price! Works great for my 622, and also for my upconverting DVD player that delays the video. BTW, the 622 used to be very bad on lip sync, but has gotten much better recently. It still varies program-to-program and channel-to-channel. Good Luck!
Brad
http://www.lipfix.com/felstondd540orders.html
The newer DD740 is now available (I have the 540) at a cheaper price! Works great for my 622, and also for my upconverting DVD player that delays the video. BTW, the 622 used to be very bad on lip sync, but has gotten much better recently. It still varies program-to-program and channel-to-channel. Good Luck!
Brad
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nexsen
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AV receivers' lip-sync features won't solve the problem
TMOCA, you mentioned waiting and buying an av receiver "that includes the lip-sync correction" feature. Take a CLOSE look before you do that because none that I've seen on the market do an adequate job of lip-sync correction. Perhaps another member has seen one and if so I hope they will report how it makes the delay adjustment and how much delay it offers.
Most don't have enough delay (some as little as 80 ms) but even if they did have sufficient delay the way they have implemented the adjustment makes it essentially impossible to ever achieve lip-sync. AV receiver manufacturers seem to think the only problem is the fixed video delay added by your display but in reality the lip-sync error already present in the arriving signal often exceeds the display's delay and it changes from time to time.
For true lip-sync correction you need to be able to fine tune the audio delay while watching your program without image disturbance. It's not unusual for lip-sync errors to swing by 100 ms from one program or DVD to the next. I'm on Time Warner and this TV season some programs require as little as 21 ms delay from my DD740 (like Dirty Sexy Money) while others (like Cane) require 124 ms. To make these adjustments with an av receiver's audio delay embedded in a set-up menu overlaying the screen would be impossible for several reasons: Talking heads suitable as targets for the adjustment don't always appear at the start of each new program and DVD and stay on screen long enough. You may end up several minutes into the program and even then you might have to tweak it a little later in the program to get it right.
Three manufacturers now make delay boxes to "do lip-sync correction" right. Felston was first in 2004 (I bought their single input DD340 back then) and both Primare and Alchemy2 now offer dedicated audio delays that cost as much or more than many new av receivers claiming such a feature. So, these products are not just intended to add lip-sync correction to old receivers that don't have such a feature but are designed to give all receivers - even those that "claim" a lip-sync delay feature the "real lip-sync correction" capabilities needed to actually do the job right.
With all three dedicated digital audio delays on the market (Alchemy2, Felston, and Primare) you make these adjustments "on-the-fly" as you watch with no image disturbance. You just touch the + or - buttons and the audio shifts until it looks perfect. These boxes have a lot of other features but that's the essential feature for lip-sync correction - that you can tweak for perfect sync without disrupting what you are watching (and my DD340 did that) and of course you need sufficient delay but all these new boxes have over 600 ms.
There's a review of all three:
http://www.audaud.com/article.php?ArticleID=3011
The Felston DD740 is listed in that review at $249 but it's actually $199 now which is even less than I paid for their single input DD340 back in 2004 and less than half the price of some of the other units that don't do as much. My new four input DD740 has more features (more presets, direct numeric entry, finer setting adjustment, etc.) than the others but it does not have RS232 control. I use IR and don't need RS232 but if you have an older control system and need that you will need the Alchemy2 or Primare and have to give up those other user features.
But even the DD740 (which came out in 2007) with its aggressive $199 price still costs as much as some new low-end receivers that claim a lip-sync delay so my point is these companies certainly would not have produced these complex relatively expensive products if they simply offered the same inadequate lip-sync control that receivers do.
Most don't have enough delay (some as little as 80 ms) but even if they did have sufficient delay the way they have implemented the adjustment makes it essentially impossible to ever achieve lip-sync. AV receiver manufacturers seem to think the only problem is the fixed video delay added by your display but in reality the lip-sync error already present in the arriving signal often exceeds the display's delay and it changes from time to time.
For true lip-sync correction you need to be able to fine tune the audio delay while watching your program without image disturbance. It's not unusual for lip-sync errors to swing by 100 ms from one program or DVD to the next. I'm on Time Warner and this TV season some programs require as little as 21 ms delay from my DD740 (like Dirty Sexy Money) while others (like Cane) require 124 ms. To make these adjustments with an av receiver's audio delay embedded in a set-up menu overlaying the screen would be impossible for several reasons: Talking heads suitable as targets for the adjustment don't always appear at the start of each new program and DVD and stay on screen long enough. You may end up several minutes into the program and even then you might have to tweak it a little later in the program to get it right.
Three manufacturers now make delay boxes to "do lip-sync correction" right. Felston was first in 2004 (I bought their single input DD340 back then) and both Primare and Alchemy2 now offer dedicated audio delays that cost as much or more than many new av receivers claiming such a feature. So, these products are not just intended to add lip-sync correction to old receivers that don't have such a feature but are designed to give all receivers - even those that "claim" a lip-sync delay feature the "real lip-sync correction" capabilities needed to actually do the job right.
With all three dedicated digital audio delays on the market (Alchemy2, Felston, and Primare) you make these adjustments "on-the-fly" as you watch with no image disturbance. You just touch the + or - buttons and the audio shifts until it looks perfect. These boxes have a lot of other features but that's the essential feature for lip-sync correction - that you can tweak for perfect sync without disrupting what you are watching (and my DD340 did that) and of course you need sufficient delay but all these new boxes have over 600 ms.
There's a review of all three:
http://www.audaud.com/article.php?ArticleID=3011
The Felston DD740 is listed in that review at $249 but it's actually $199 now which is even less than I paid for their single input DD340 back in 2004 and less than half the price of some of the other units that don't do as much. My new four input DD740 has more features (more presets, direct numeric entry, finer setting adjustment, etc.) than the others but it does not have RS232 control. I use IR and don't need RS232 but if you have an older control system and need that you will need the Alchemy2 or Primare and have to give up those other user features.
But even the DD740 (which came out in 2007) with its aggressive $199 price still costs as much as some new low-end receivers that claim a lip-sync delay so my point is these companies certainly would not have produced these complex relatively expensive products if they simply offered the same inadequate lip-sync control that receivers do.
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videoengr
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The main problem with lip-sync issues is that television programming goes through so many different production and distribution paths and most of those do not adequately add audio delay to compensate for the delay of the video signal processing. Consequently by the time the viewer sees the program, the relative timing of audio and video are completely random. The problem is discussed in more detail in Wikipedia - search audio/video synchronization. There are instruments which can measure the relative timing of audio and video, including one which measures the lip sync error of programming real time (it works like the human brain to match sounds to the lip shape that creates them - see www.pixelinstruments.tv). Unfortunately the various companies involved in the program production and distribution (like networks, TV stations, Dish Networks and Direct TV) for the most part don't want to invest in the equipment. These companies will ignore the problem until viewers like you and me complain loudly enough. I noticed a lot of lip sync problems on my local TV stations but whenever I called them they blamed the networks. I wrote to the networks but never got a response. The lip sync problems got a lot smaller and happened much less often when I called some of the local advertizers on the station's evening news and pointed the lip sync problems out to them. The station managers then spent the money to buy the equipment to help fix the problem.
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nexsen
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I fully agree with VIDEOENGR and his suggestion to exert economic pressure on TV stations to do a better job of lip-sync is a good one. You also may be able to use some scientific research done at Stanford University which proved viewers find out of sync material "less persuasive" even when they don't notice it is out of sync. Advertisers won't like that!
Here's a link (also to Pixel Instruments which VIDEOENGR mentioned) to the Stanford research:
http://www.pixelinstruments.tv/pdf/Arti ... chrony.PDF
It basically says the physical impossibility of lip-sync error causes viewer's to feel characters are "more agitated, less successful, less persuasive" - even when not consciously noticed.
That basically says lip-sync error is undermining the very essence of cinema itself - our impression of the characters.
It amazes me that this industry has us fixating over things like speaker alignment - getting sound from each speaker to our ears within a millisecond of each other - but has ignored the fact that the whole sound package is arriving long before the video associated with it is seen. Many things in nature obstruct sound paths and can account for slight differences in the arrival of sound at each of our ears so that isn't really an unnatural occurrence but lip-sync error is a total contradiction of nature - it can not happen in the real world.
Since our brain's reaction is to ignore what it can not process most people don't notice lip-sync error because they are subconsciously looking away from the offending lips. Some people can ignore almost 100 ms of leading audio before consciously noticing it.
That's what makes it so hard for people to talk about and compare lip-sync error. This insidious phenomenon masks itself from view until the individual's threshold of recognition is exceeded and then becomes far more noticeable than before.
One forum contributor whose threshold of recognition has not yet been exceeded will see no problem at all while another is going crazy over the identical lip-sync error.
But if you really force yourself to "look at the lips" almost everyone will see it.
Back to correction: Until the standards are changed and a watermark is added to video and audio to define when they were originally in-sync there isn't much hope. It is currently an open loop control system where the broadcasters are "supposed to" meaure thye video delay at each DVE (digital video effect) and add an equal audio delay to keep it in sync. That already happens most of the time but if it fails at a single spot along the path from image capture through post production and broadcast the lip-sync error that creeps in cannot be detected and removed automatically down stream. And these errors that creep in are cumulative but since they are also guilty of over correction it goes both ways and is random as VIDEOENGR mentioned. Elaborating a little on the Pixel Instrument system that was mentioned: From my understanding it is not at all "automatic" but a somewhat manual process using a graphic computer to lasso the lips and track their motion in concert with the sound and even then can only get lip-sync within a frame (33 ms) which many of us still find disconcerting. In fact, the Stanford research showed the negative impact on perception at 41.25 ms so it may very well still be present at 33 ms. It would be nice to see some research using eye tracking technology at even lower sync error to see at what point we would look at the actors faces as we normally look at human faces.
Until we know at what value lip-sync error stops subconsciously impacting our perception I'm going to continue to adjust my DD740 for perfect sync. It may not need to be within a millisecond but currently all the scientific data we have (from Stanford's research) says it impacts perception even when not noticed and they did not test below 41.25 ms.
Here's a link (also to Pixel Instruments which VIDEOENGR mentioned) to the Stanford research:
http://www.pixelinstruments.tv/pdf/Arti ... chrony.PDF
It basically says the physical impossibility of lip-sync error causes viewer's to feel characters are "more agitated, less successful, less persuasive" - even when not consciously noticed.
That basically says lip-sync error is undermining the very essence of cinema itself - our impression of the characters.
It amazes me that this industry has us fixating over things like speaker alignment - getting sound from each speaker to our ears within a millisecond of each other - but has ignored the fact that the whole sound package is arriving long before the video associated with it is seen. Many things in nature obstruct sound paths and can account for slight differences in the arrival of sound at each of our ears so that isn't really an unnatural occurrence but lip-sync error is a total contradiction of nature - it can not happen in the real world.
Since our brain's reaction is to ignore what it can not process most people don't notice lip-sync error because they are subconsciously looking away from the offending lips. Some people can ignore almost 100 ms of leading audio before consciously noticing it.
That's what makes it so hard for people to talk about and compare lip-sync error. This insidious phenomenon masks itself from view until the individual's threshold of recognition is exceeded and then becomes far more noticeable than before.
One forum contributor whose threshold of recognition has not yet been exceeded will see no problem at all while another is going crazy over the identical lip-sync error.
But if you really force yourself to "look at the lips" almost everyone will see it.
Back to correction: Until the standards are changed and a watermark is added to video and audio to define when they were originally in-sync there isn't much hope. It is currently an open loop control system where the broadcasters are "supposed to" meaure thye video delay at each DVE (digital video effect) and add an equal audio delay to keep it in sync. That already happens most of the time but if it fails at a single spot along the path from image capture through post production and broadcast the lip-sync error that creeps in cannot be detected and removed automatically down stream. And these errors that creep in are cumulative but since they are also guilty of over correction it goes both ways and is random as VIDEOENGR mentioned. Elaborating a little on the Pixel Instrument system that was mentioned: From my understanding it is not at all "automatic" but a somewhat manual process using a graphic computer to lasso the lips and track their motion in concert with the sound and even then can only get lip-sync within a frame (33 ms) which many of us still find disconcerting. In fact, the Stanford research showed the negative impact on perception at 41.25 ms so it may very well still be present at 33 ms. It would be nice to see some research using eye tracking technology at even lower sync error to see at what point we would look at the actors faces as we normally look at human faces.
Until we know at what value lip-sync error stops subconsciously impacting our perception I'm going to continue to adjust my DD740 for perfect sync. It may not need to be within a millisecond but currently all the scientific data we have (from Stanford's research) says it impacts perception even when not noticed and they did not test below 41.25 ms.
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videoengr
- Member
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- Joined: Sun Jun 25, 2006 6:03 pm
Lip Sync errors
Nexsen makes some very good points about both the causes and effects of lip sync errors. In particular the explanation about the threshold of recognition points out an effect which has only recently been recognized.
There was an excellent paper on this threshold of recognition effect, and lip sync problems in general, which was presented at the 2007 National Association of Broadcasters convention. The paper, titled Audio-Video Timing was given by Paul Briscoe, Manager, Strategic Engineering at Harris Broadcast Communications Corp. in Toronto, Canada. I think that used to be Leitch Corp.
Unfortunately I can't find a free copy of this paper on the internet. It is available for $150 as part of the full conference proceedings (ISBN: 0893243914) at http://bookshop.blackwell.com/jsp/id/NA ... 0893243913. For anybody who is interested in the technical details behind the problem and its effects. Perhaps somebody knows where a copy can be obtained for download at a more reasonable price.
There was an excellent paper on this threshold of recognition effect, and lip sync problems in general, which was presented at the 2007 National Association of Broadcasters convention. The paper, titled Audio-Video Timing was given by Paul Briscoe, Manager, Strategic Engineering at Harris Broadcast Communications Corp. in Toronto, Canada. I think that used to be Leitch Corp.
Unfortunately I can't find a free copy of this paper on the internet. It is available for $150 as part of the full conference proceedings (ISBN: 0893243914) at http://bookshop.blackwell.com/jsp/id/NA ... 0893243913. For anybody who is interested in the technical details behind the problem and its effects. Perhaps somebody knows where a copy can be obtained for download at a more reasonable price.