jayselway Posted November 10, 2006 Share Posted November 10, 2006 Hello all, I have just completed an AV install in a new bar in Harrogate, which has 2 x Plasma, 2 x LCD and 1 x CRT. As spec'ced by the brewery, the whole system is controlled with a Kramer VS88V Matrix. It's got various sources (Freeview box, Sat, DVD and VHS). The screens are connected using composite, and RG59 cable. There are some long leads on the install, however, there have been no issues with picture quality on the long runs. The sound for the venue is separate, through a cloud zone mixer etc... Now, the problem I have is that on the CRT, the picture is becoming delayed somehow. On the plasma and LCD screens, the picture is in time with the sound. It's not enough to be noticeable, but I noticed it, and now it's bugging me! Is there a reason why a CRT which is the closest screen to the rack should have such an issue? Ta! Link to comment Share on other sites More sharing options...
broadcast_techie Posted November 10, 2006 Share Posted November 10, 2006 Hi, a few questions:What CRT/ Plasma.... are you using?how much is the delay? a few frames, seconds?I take it the picture is after the sound... You will find the Matrix will add up to a few frames delay:The various inputs will all be playing back out of sync, and for the matrix to re distribute the signal it needs to put them in a frame store to then play back out all at the same time. There isn't a solution to this unless all the equipment can be sync locked. That doesn't answer why the CRT is behind, but explains why there is some delay in the first place. Kris Link to comment Share on other sites More sharing options...
paulears Posted November 10, 2006 Share Posted November 10, 2006 Distance is immaterial in a venue - the delay has to be in the processing somewhere - is there a framestore, or some kind of d-a conversion in the line to the CRT monitor? Does this monitor have some kind of scaling or screen manipulation maybe 16:9 to 4:3. The switcher doesn't have any processing as far as I know - so the monitor is the likely culprit - I seem to remember some of the old 100Hz Philips had a very short delay as they had a frame store to do the double rate readout. These often appeared out of the corner of your eye to switch a bit late - but the delay was not obvious front on? Link to comment Share on other sites More sharing options...
jayselway Posted November 10, 2006 Author Share Posted November 10, 2006 Cheers guys, it's a 4:3 Panasonic CRT, which the manager has decided has to stay (looks a bit ugly!), everything else is in 16:9. As I mentioned the plasma's are pretty much in time with the audio, there is the smallest delay there, but that's due to the switcher. I'm not sure if it has a framestore or not. The plasma's are all different makes, as are the LCD's - 1 x Hyundai Plasma, 1 x Hitachi 60" Plasma, 1 x Relysys LCD and 1 x Samsung LCD. It's one of those jobs where I was basically the fitter of the second hand kit the manager had got hold of beforehand. Thanks again :huh: Link to comment Share on other sites More sharing options...
soundo26 Posted November 10, 2006 Share Posted November 10, 2006 are they all running from the same tuner? Link to comment Share on other sites More sharing options...
jayselway Posted November 10, 2006 Author Share Posted November 10, 2006 There are two freeview boxes in the rack (via aerial distribution), and those feed into the Kramer. One LCD screen has an internal tuner for freeview, however that's only used to show a different channel from the rest of the system. Link to comment Share on other sites More sharing options...
henny Posted November 12, 2006 Share Posted November 12, 2006 so lets get this right your sigmal path is sorce (Freeview box, Sat, DVD and VHS). > Swithcher >DA > 2 x Plasma, 2 x LCD and 1 x CRT if this is so all it can be is the TV, ian Link to comment Share on other sites More sharing options...
Chris Beesley Posted November 12, 2006 Share Posted November 12, 2006 This might sound a little silly - but have you tried switching the leads over on the back of the switcher? For a two minute job its worth a try... Link to comment Share on other sites More sharing options...
Andrew C Posted November 12, 2006 Share Posted November 12, 2006 This is really quite odd. I am aware that flat panel displays can be delayed by the internal processing, but not CRTs. Are you sure its not the other way round? Link to comment Share on other sites More sharing options...
jayselway Posted November 13, 2006 Author Share Posted November 13, 2006 I've tried the obvious checks, like swapping outputs on the Kramer, and leads as far as I can. It's not as bad as it was, I can see it, but the roadie looked at me staring at it, and said "there's nothing wrong with it, go for the butties!" That's me told! your signal path is source (Freeview box, Sat, DVD and VHS). > Switcher >DA > 2 x Plasma, 2 x LCD and 1 x CRT Not quite, path is here (cue another dodgy paintbrush drawing!) Linky Just seemed a little odd really, I agree if anything the delay would be slightly more on the digi-screens, but no, it's definitely on the CRT. Link to comment Share on other sites More sharing options...
dbuckley Posted November 13, 2006 Share Posted November 13, 2006 And you are definitely definitely using the same source for all displays... Link to comment Share on other sites More sharing options...
paulears Posted November 14, 2006 Share Posted November 14, 2006 this is going around in circles. For goodness sake, just swap the crt for a plasma and see if the delay stays with the crt - almost certainly it will, meaning the crt has a frame store inside. Nothing in your descriptions indicates anything other than this. If you walk into currys or comet and stand and watch their displays, you see a few appear out of the corner of your eye to be behind - the delay is tiny - I'd guess a single frame at worst, but it is there. Link to comment Share on other sites More sharing options...
jayselway Posted November 15, 2006 Author Share Posted November 15, 2006 Paul, I did that, and yes, it stayed with the CRT. The discussion continued, so I provided more information, as requested. :( Once again, thanks all for your replies and help! :huh: Link to comment Share on other sites More sharing options...
James Posted November 22, 2006 Share Posted November 22, 2006 Cheers guys, it's a 4:3 Panasonic CRT, which the manager has decided has to stay (looks a bit ugly!), everything else is in 16:9. Does this mean you have center cut out and anamorphic sources available on the matrix? or are you running the 16:9 displays pilarbox? James Link to comment Share on other sites More sharing options...
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