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** WARNING ** to ALL Plasma Owners


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Hi All,

Over the past few days I have been installing a new plasma in my home 'theatre' - after 6 months on this forum flip-flopping towards a full replacement of the huge mistakes I made with my first DTV purchase (described here in my first post).

I was determined not to repeat any of those mistakes and - with huge thanks to all the experts on this forum who have helped me along the way - I don't think I have made any [yet]!

So now I want to pass on some things I have learned at home this week to:

- current plasma owners experiencing niggling problems with their setup; and,

- potential plasma buyers who might not be expecting these issues.

  • If you are having lip-synch problems from all sources, then you need an HT receiver or pre-amp/processor that allows setting of an audio delay!
    My Onkyo THX receiver has an 'AV Delay' setup option that increments/decrements the delay in 0.5 millisecond steps. I don't know what other receivers do this, but it is best done as a global setting rather than for each speaker individually. Also note that my panel has no tuner and I don't use its audio inputs - so the panel is not doing its own audio delay internally.
    These digital displays do a lot of processing on the analogue or digital input signals - resulting in the sound coming out of the speakers while the display is still in the middle of re-sizing to native resolution, followed by gamma adjustment, and noise processing, and .... !
  • If you are experiencing 'clay faces', then you must not use a composite input!
    You know, the yellow RCA lead that was the only option with the cables the bas***** they provided you?! Immediately switch to at least S-Video, but preferably RGB or YUV or, best of all, DVI inputs. The very limited colour depth in the composite signal plays havoc with most plasmas (even mine!).
  • If you are experiencing 'jelly face' (trailing eyes, etc) on any locally produced programs (ie. not the worst US delayed broadcasts like 'Jim Lehrer' on SBS - even mine goes to jelly with that), then you need to upgrade your panel - because mine doesn't!
  • If you are experiencing 'noise' in the picture then upgrade your cabling - both RF input (to better shield it) and video interconnects (to better protect them from picking up interference from RF leads and other nearby video leads).
    RF leads must be at least double-shielded - foil to shield high frequencies (RF pickup) and braid to shield low frequencies (mains pickup). Quad-shield (2 x foil + 2 x braid) doubles this protection. Video interconnects operate at very high frequencies and therefore require exactly the same protection.
    There are excellent quality YUV/RGB interconnects available for just $15 if you haggle hard at the retail chains (I aim for 50% off!). If you can possibly afford it, get a set and use the ones that came with the STB to hang some paintings.
  • If you see any visible 'digital artifacts' with the NineHD Loop (1920x1080 in Brisbane) on your panel then you need to upgrade your panel or STB or both! I see absolutely no macroblocking or posterisation or jaggies or moire or movement blurrs whatsoever on my panel with a DVI HD-STB.
  • If you are tight on space for a 5.1 speaker setup, consider using the 'wing' speakers on the panel as a Centre channel instead of buying a separate centre channel speaker. This requires some audio knowledge and tinkering with pre-amp settings for an acceptable result, but WAF improves considerably by not having a large speaker in front of, or on top of, the panel. See my results here, if you are interested. At least the centre channel audio 'image' from these speakers will be at the dead centre of the screen! Warning: They will not blend in well with good quality speakers!!

If I discover or think of anything else I'll let you know. :blink:

Regards to all,

Ian

Edited by ijd
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Hi All,

Over the past few days I have been installing a new plasma in my home 'theatre' - after 6 months on this forum flip-flopping towards a full replacement of the huge mistakes I made with my first DTV purchase (described here in my first post).

I was determined not to repeat any of those mistakes and - with huge thanks to all the experts on this forum who have helped me along the way - I don't think I have made any [yet]!

So now I want to pass on some things I have learned at home this week to:

- current plasma owners experiencing niggling problems with their setup; and,

- potential plasma buyers who might not be expecting these issues.

  • If you are having lip-synch problems from all sources, then you need an HT receiver or pre-amp/processor that allows setting of an audio delay!
    These digital displays do a lot of processing on the analogue or digital input signals - resulting in the sound coming out of the speakers while the display is still in the middle of re-sizing to native resolution, followed by gamma adjustment, and noise processing, and .... !
  • If you are experiencing 'clay faces', then you must not use a composite input!
    You know, the yellow RCA lead that was the only option with the cables the bas***** they provided you?! Immediately switch to at least S-Video, but preferably RGB or YUV or, best of all, DVI inputs. The very limited colour depth in the composite signal plays havoc with most plasmas (even mine!).
  • If you are experiencing 'jelly face' (trailing eyes, etc) on any locally produced programs (ie. not the worst US delayed broadcasts like 'Jim Lehrer' on SBS - even mine goes to jelly with that), then you need to upgrade your panel - because mine doesn't!
  • If you are experiencing 'noise' in the picture then upgrade your cabling - both RF input (to better shield it) and video interconnects!
    There are excellent quality YUV/RGB interconnects available for just $15 if you haggle hard. If you can possibly afford it, get a set and use the ones that came with the STB to hang some paintings.

I'll add to this in the morning .....

Ian

Cheers for the info Ian! I have a Yamaha reciever that has adjustable delays to all speakers... bit of a hassle though. Atleast I know I can get around the "lip sync" issue if I need to.

Ta

MB

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Cheers for the info Ian! I have a Yamaha reciever that has adjustable delays to all speakers... bit of a hassle though. Atleast I know I can get around the "lip sync" issue of I need to.

Ta

MB

That delay is actually for setting speaker distance - you may struggle getting enough adjustment for display screen delay. But it is a nice workaround!

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Some good points there Ian I love the bit about using the trwaway cables that come in the box to hang up paintings! hehehe - I've always wondered what to do with those things.

I have'nt had any lips synch dramas (thank god! - not sure what I'd do if I did) yes as Nobby said I'd rather just use the HT amp delays to compensate for the speaker distances but interesting work around - I guess you'd add the required delay to all the speakers? to what the calculated delay should be?. Also I'm sure I remember seeing a little black box for sale somewhere to get over lip synch delay woes. Also I think some components come with adjustable delay for this reason - cannot remember any - must be too early on a sat morning after a late one the night before.

I think theres some very valuable stuff their, especially in your origianl post for any newbies out there (I'm sorry I could not help laughing when I got to the bit that the vcr remotes simultaneuosly change the tv channels - that would be frustrating!) Thats something else to check before you buy make sure all your remotes don't clash!

I think it pays to do your own research - I too spent pretty close to 6 months flip-flopping too but I think the time helped to ensure I got the best on the market and what I bought was a considered purchase and not a impulse buy or "mistake" as you call it.

Without this forum I would have had no hope of getting what I have now and probably would have ended up going along to myer megamart or HN and walking out with one of those 480p panel(thinking I got an extraordinary deal - wow $4000 for a plasma?) and probably still wondering why it didn't look as good as the other panels in the shop even though I'd hooked a craptech HD box upto it.

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I have'nt had any lips synch dramas (thank god! - not sure what I'd do if I did) yes as Nobby said I'd rather just use the HT amp delays to compensate for the speaker distances but interesting work around - I guess you'd add the required delay to all the speakers? to what the calculated delay should be?. Also I'm sure I remember seeing a little black box for sale somewhere to get over lip synch delay woes. Also I think some components come with adjustable delay for this reason - cannot remember any - must be too early on a sat morning after a late one the night before.

All,

I've just added this para into the top post to explain what I mean a bit better: :blink:

"My Onkyo THX receiver has an 'AV Delay' setup option that increments/decrements the delay in 0.5 millisecond steps. I don't know what other receivers do this, but it is best done as a global setting rather than for each speaker individually. Also note that my panel has no tuner and I don't use its audio inputs - so the panel is not doing its own audio delay internally."

Hope that helps,

Ian

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No lip-sync. issues with my Hitachi either....

I am surprised there are such issues with the NEC, usually it is presented by external scaler/s. I guess NEC must be doing a lot more video processing in software.

IF there are lip-sync. issues, apart from the solution you described regarding delay-compensation in the receiver; there MAY be another solution. I suspect you may be able to route the Sound (only 2 channel though), via the NEC, coz if it is doing the processing most probably it will also provide for the audio to be synchronized IF it is routed through the TV. You will need to experiment, as a quick check ensure that the NEC has Video out and Audio outs (in addition to its hosts of inputs....)... I suggest this, coz many scalers do provide inputs and outputs for audio, to actually re-sync. the audio; such that no additional tinkering is required...

Nice post Ian,

cheers,

Ritesh

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[*]If you see any visible 'digital artifacts' with the NineHD Loop (1920x1080 in Brisbane) on your panel then you need to upgrade your panel or STB or both! I see absolutely no macroblocking or posterisation or jaggies or moire or movement blurrs whatsoever on my panel with a DVI HD-STB.

Some good tips for the Plasma "seekers" (personally i'd could never handle going so small coming from a PJ :blink: )

THough im not sure about what you say above. I have watched the Demo on various equipment, and while i will agree than some HD STB are better than others at the issues you discribe, these issues to some degree are in the broadcast (In Brisbane atleast) and no doubt due to insufficent bitrate.

It occurs on my HTPC on a monitor.... and on my PJ. Now in this case ALL the "deinterlacing" etc is being done on the PJ so it is not a display artifact. It happens with any video codec/filter used.

Perhaps your display is perhaps doing some smart masking of this during its deinterlacing or similar?

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[*]If you see any visible 'digital artifacts' with the NineHD Loop (1920x1080 in Brisbane) on your panel then you need to upgrade your panel or STB or both! I see absolutely no macroblocking or posterisation or jaggies or moire or movement blurrs whatsoever on my panel with a DVI HD-STB.

Some good tips for the Plasma "seekers" (personally i'd could never handle going so small coming from a PJ :blink: )

THough im not sure about what you say above. I have watched the Demo on various equipment, and while i will agree than some HD STB are better than others at the issues you discribe, these issues to some degree are in the broadcast (In Brisbane atleast) and no doubt due to insufficent bitrate.

It occurs on my HTPC on a monitor.... and on my PJ. Now in this case ALL the "deinterlacing" etc is being done on the PJ so it is not a display artifact. It happens with any video codec/filter used.

Perhaps your display is perhaps doing some smart masking of this during its deinterlacing or similar?

I repeat: "no digital artifacts whatsoever on the Brisbane NineHD loop". The evidence is here in front of me - and I receive the same broadcast from the same MtCoottha tower that you do!

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What the bit where the bird is on the tree (lorakeet thingy). When it shakes its head and when it flys off there is definate pixelation, due to lots of fast movement this is expected at the broadcast bitrate.

If it does not appear.... then id be pretty certain your display "may" have some kind of "smarts" to combat such...... or maybe even you set top.

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Cheers for the info Ian! I have a Yamaha reciever that has adjustable delays to all speakers... bit of a hassle though. Atleast I know I can get around the "lip sync" issue of I need to.

Ta

MB

That delay is actually for setting speaker distance - you may struggle getting enough adjustment for display screen delay. But it is a nice workaround!

Well my (fairly low end) yamaha receiver certainly does have a separate delay for use on lip sync, not just the speaker delay stuff. I dont use it of course!

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What the bit where the bird is on the tree (lorakeet thingy).  When it shakes its head and when it flys off there is definate pixelation,  due to lots of fast movement this is expected at the broadcast bitrate.

If it does not appear.... then id be pretty certain your display "may" have some kind of "smarts" to combat such...... or maybe even you set top.

Nah! Its just Ian's glasses - give 'em a clean and you'll see it! :blink::P

Just kidding ... I think!

NB: Nice work, Ian, well put. Not that I'll be buying plasma, but if I were ...

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What the bit where the bird is on the tree (lorakeet thingy).  When it shakes its head and when it flys off there is definate pixelation,  due to lots of fast movement this is expected at the broadcast bitrate.

I'll get back to you on the lorikeet? I hadn't heard of this and have never noticed it either! :P:blink:

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What the bit where the bird is on the tree (lorakeet thingy).  When it shakes its head and when it flys off there is definate pixelation,  due to lots of fast movement this is expected at the broadcast bitrate.

I'll get back to you on the lorikeet? I hadn't heard of this and have never noticed it either! :P:blink:

Hi spoonfed, I'm back!

If you are referring to what I would call a white 'sulphur-crested cockatoo?' - but I wouldn't know a swan from an eagle! - taking off into the lower left corner, then I can honestly tell you that there was no pixelisation?! Plenty of blur, but the NEC does a muuuuch better job than my Fusion/1280x1024-LCD/P42.4 combination!!

aahhhh ... OK, the grey one with the red breast is fine too - as is the rosella scratching its chin at a rapid clip!! Don't blame bit-rates any more dude - Perth gets an even better rate than we do, and mine's perfect!

If you mean one of the other birds, just post a rough desc and I'll check.

Cheers,

*** This thread is not meant to be a plug for XXX - I've tried to not mention it by name - I'm only trying to show that is IS possible to get perfect digital PQ from the Nine HD Loop (in Brisbane) as a basis for comparing different technologies, HD models, aerials, interconnects, shop setups, ... whatever! BTW, my panel is only 1024x768 native. ***

I would love to hear from a Nine engineer with access to the source and a studio monitor to confirm that they think they are broadcasting a perfect picture - irrespective of bit-rate. 'Cos I NOW think that broadcast bit-rates have been falsely accused for the crimes of the panel electronics for way too long!!!

IMHO, by bringing the XXX into this forum, Glenncol has accidentally (:P) pointed Angelo then me into acquiring THE new reference in digital displays - of any type! My opinion ... flames welcome!

Edited by ijd
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What the bit where the bird is on the tree (lorakeet thingy). When it shakes its head and when it flys off there is definate pixelation, due to lots of fast movement this is expected at the broadcast bitrate.

Another part to look at is the flags at the US open to the left of Pete Samfras!! :blink:

cheers laurie

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If you are referring to what I would call a white 'sulphur-crested cockatoo?' - but I wouldn't know a swan from an eagle! - taking off into the lower left corner, then I can honestly tell you that there was no pixelisation?! Plenty of blur, but the NEC does a muuuuch better job than my Fusion/1280x1024-LCD/P42.4 combination!!

I think the panel or STB scans for compression artifacts and smoothes them out or you're sitting far enough away not to notice them.

Broadcast bitrates for HD are definately not high enough but we can't do much better because of SD channels using up some of the available bandwidth. What can be done better is optimising the mux and minimising the size of the null stream to about 450 to 500kbits with any bandwidth spared allocated to the HD channel and I'd like to see SD bitrates kept at or under 6mbits. Anything over 6mbits for SD is a waste.

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Somehow,somewhere,someone is running HD down to the point where everyone will say "Might as well do away with HD it's crap" we have seem to be going backwards not forward... gee at one point Ten I thought was way ahead :blink:

cheers laurie

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Somehow,somewhere,someone is running HD down to the point where everyone will say "Might as well do away with HD it's crap" we have seem to be going backwards not forward... gee at one point Ten I thought was way ahead :blink:

cheers laurie

That day is at risk of getting closer when ABC switch to 576p ED to support their VPG and ABC2. Three out of five networks will be broadcasting ED then which is seems really bad but if you ignore the government broadcasters who upconvert everything there's only one network that broadcasts ED, 4+3.

I'm lucky that Nine Perth treat HD well unlike most of the other Nine stations. There's room for improvement on Nine Perth such as some mux tweaking to reduce the null stream and transfer any gains to the HD channel.

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By the way, the start to my post was just to let people know that interlaced or not has nothing to do with pixelation.

I was going to raise this with DA, too, Michael.

In my 'Duck Problem' cap I noticed both combing (caused by camera+duck+water movement between interlaced fields) and mpeg macroblock breakup (pixellation - caused by source over-compression or my decoder failing to keep up?). The breakup is particularly noticeable right along the stick the duck is swimming over.

In general, I am extremely happy with Nine's HD loop as it allows me to look for telltales (yes, even flaws like the one we are discussing) to help make a final decision on an HD display device that will have to last me for years - since whatever I buy now will be worth stuff-all to sell in a year or so.

DA and I (with Owen's help) have thrashed the 720p v. 1080i issue in the past and there is no argument from me that 720/50p (nearly double the res of 576p) would be best for HD sport and action movies (but only 4+3 might be gearing up for this in Oz) while the further doubling of resolution to 1080i is best for general HD viewing of studio, documentary, drama, sitcom, movie and news/current affairs. Sport looks great in 1080i also, but there are obvious movement artefacts on fast camera pans.

I am also very happy (ecstatic, actually) with 720p @ 56Hz (can't get down to 50Hz) on my small 17" LCD in the study - but I'm still gunning for a native-1080i display for any new purchase.

Ian

And with the ducks splashing in the pond Ian (captured by your self a while back) wondering if this showing up without pixelation on the NEC? - if it is surely the NEC is doing something to clean up the image. I can definetely see the pixelation in this scene on my hitachi. Have always considered these type of artifacts coming from the source material. I have never seen this kind of thing on dvd.

My own personal opinion - the loop, as brilliant as it is, is flawed in sections. I've seen this pixelation even on the sony kvhr36 crt tv and hence believe this is not a plasma induced thing and is in the source material (there are other examples just like this). I would not be suggesting people use the loop to test out plasmas - I'd be using dvds and other live tv such as the panel.

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Al, I have taken particular interest in the duck problem - it's a family thing!

I can assure you that it appears faultless ... except ... for some macroblocking just on the underwater reed that the duck swims over. And I'm not even sure that this is not natural?!

Another [Melbourne] example is a tall apartment building in Southbank behind and to the right of the Southbank restaurants. It is called Southbank Towers and I used to live in it. Every time it comes on I look for a number of things that have tripped every other display: resolution (to see how much pf my old balcony's detail is visible), jaggies (very slight angle lines of balcony rails) and moire (from poor rescaling of all the windows). This sucker beats them all!!

End of praise for the NEC! Everything I have to say about it has been said in my last few days' posts. Believe it if you will ... I'm now moving onto some further upgrades and will see ya's all in other threads!

Cheers and regards,

Ian

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Just to reply to Spoonfed here on the de-interlacing issue - I have done lots of testing lately between my projector, sony KVHR36M31, HTPC (with a radeon 9200) and Marantz DV6400. I have found that from my system the HTPC cannot be used as a reference for de-interlacing. There are several scenes in various movies that I have checked between displays and sources and the HTPC is not as perfect as it may seem in the de-interlacing department, or particularly in the reading of the proper flags off the dvd. I'm not sure if this is the software or hardware but comparing some HD stbs to a VP or DVICO it is equally comparable if not shifting towards the STB's these days,

Test it out see what you think.

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This will somewhat depend on the graphics card if one is using DxVA.

I have compared 9 HD demo using VP/Dvico card.... this is irrelvant (ie the card) as i can choose the codec/filter/render etc with Digital Watch anyways.. STB was Toshiba (i think hhaha) and another one (was a while ago) and HTPC was better.

Using DxVA on Radeon 9600pro i have not encountered any Deinterlacing issues with various sources, i HAVE seen issue on other peoples set top soltuions,, here though it could be the box or it could be the display.

With software rendering, which is what i use for playback with FFDShow, yes, here de-interlacing of video captured source (ie shows like news stories etc) can have issues depending on the codec. I live with this as i don't really watch any of this for "playback" and DVD"s are all filim based, same with the shows i watch, film or progressive based so have zero issues. Small price to pay for what good MPEG2 filter + FFDShow can offer over a stand along DVD player.

Acutally on that topic Swedish Chef off HT Central is gonna bring his Denon 2900 round to do some comparos. Im thinking i should make a DVD based from good DTV source as i never demo PQ using DVD movies as good DTV shows look better. (im talking SD here..... though these shows are usually HD/ED produced)

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If you are referring to what I would call a white 'sulphur-crested cockatoo?' - but I wouldn't know a swan from an eagle! - taking off into the lower left corner, then I can honestly tell you that there was no pixelisation?!

I think the panel or STB scans for compression artifacts and smoothes them out or you're sitting far enough away not to notice them.

Pixellation or blocking that Ian does not see, that others may refer to, may also be due to Ian's digital reception being better with a low received error count.

So even if it is not Ian's dirty spectacles, someone with an identical STB & Display, may experience more or less problems due to different reception parameters, antenna, RF cables etc.

Cheers

JB

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