***Official Digital Video Essentials Discussion Thread*** (2 Viewers)

[PaulBigelow]

A man with one watch knows what time it is. A man with two watches is never quite sure.

 

[Thomas Smailus]

I'll ammend that as follows:

A man with one watch thinks he knows what time it is. He lives in ignorant bliss.

A man with two watches is not sure what time it is exactly, but knows one of his watches at least is wrong.

Both men will probably get to thier appointments on time.

 

[Edward J M]

I went back and calibrated video with Avia this weekend.

Avia settings:

1) Contrast: 43%
2) Brightness: 33%
3) Color: 36% (for blue which yields a mild 5% red push)
4) Tint: centered
5) Sharpness: 40%
6) Color Temp: warm (most natural grays to my eye)

These settings were a bit different than for DVE, especially for the sharpness. The sharpness was easier to see with the color off (Avia recommends this) and I started to see "ringing" around the letters on the test pattern at anything over 40%. Picture grain is considerably less at 40% (as opposed to 63% with DVE) and with no loss in resolution (at least to my eyes).

Overall, I found Avia to be superior to DVE with respect to navigation, menus, and explanations of what I am "supposed" to be seeing on the video test patterns.

The bass level issue? Avia and DVE are sure different and I won't use DVE. I used Avia a few dB hot for HT and to my ear it sounded good - powerful without being overbearing.

Avia is Dolby Digital and uses the surround channels for sub calibration and therefore allows the surround speaker in question to contribute bass to the subwoofer tone.

I have found that the amount of bass each surround speaker contributes to the sub tone is highly dependent on its room location, its inherent bass capabilities, and the xo you have selected.

For example, my left main is several dB higher than any other channel on the subwoofer tone. If I was unfortunate enough to select the left main for sub calibration, it would result in undercalibration of the sub.

The best way to check all of the differences in the surround channels is to power down the subwoofer and run the Avia sub test tone for each channel and note the results.

If you like your bass a bit hot, pick the surround channel that has the lowest reading with the sub powered down and then use it to calibrate the subwoofer.

Regards,

Ed

 

[Dave H]

From a previous post (121) it looks like Avia is wrong since it agrees with the original VE.

Only if the DVE is correct. I just don't see how every other disc is now wrong and DVE is correct. (Admittingly, I haven't gone through and read every post.)

Actually, I am a bit more concerned with the video calibrations. From what Edward is saying, it looks better with Avia.

 

[Dave H]

From a previous post (121) it looks like Avia is wrong since it agrees with the original VE.

Only if the DVE is correct. I just don't see how every other disc is now wrong and DVE is correct. (Admittingly, I haven't gone through and read every post.)

Actually, I am a bit more concerned with the video calibrations. From what Edward is saying, it looks better with Avia.

 

[John.Meer]

It is not unthinkable that there is a consistent error in bass levels on many disks and preamps/receivers. I have a "THX certified" preamp that failed to pass all the bass channels correctly even though it had been "thoroughly tested by Dolby Labs and THX". I would like to know how DSP/software typically gets designed and tested. Do preamp/receiver manufacturers program ground-up, or do they make use of Cirrus, Motorola, etc. software for basic routines like levels?

The one or more watch analogy really hits the nail on the head. Who is to say this does not affect the test material available to the manufacturers?

 

[JasonBrown]

I connect my DVD player via Component cables to Input 3 on the TV. Satellite receivers are both via S-Video to Input 1 and Input 2. To calibrate my satellite receivers via the DVE disc, I'll need to connect the DVD via S-video, write down the calibrated values, and then use those values for Input 1 and Input 2, right? I assume the TV has a distinct set of brightness, contrast, etc.. settings for each input?

And then to calibrate Input 3 for DVD, i'll need to re-hook the DVD player using Component and re-calibrate, right?

 

[George_W_K]

After reading this thread, it seems that there are more negative things about this disc than positive. That's unfortunate, because I was looking to finally buy a calibration disc.

 

[Thomas Smailus]

George,

Just because more negative things have been said, do not let that discourage you from purchasing DVE.

The majority of what you find on such a thread, MUST BE criticisms or problems. It does little good for folks to post 'Yeah, it works great for me'. We get a lot of posts that add little usefull information to the DVE thread other than from a marketing/sales motivation standpoint. You usually get questions from folks that have an issue with it, as they are seeking help or some feedback on their thoughts.

What has become clear is that the whole concept of calibrated audio levels is a bit of a 'voodoo science', in that it certainly seemed at the time VE came out, that it was accurate, and the other products of that era agree with that understanding. Now the folks who make it, in light of the LFE issue with DVE, are suggesting they may have had problems with VE back in the day. It is possible every other disk maker also had similar problems back then (Avia, etc) but since we only have those old discs there is nothing new of theirs to compare it to. It could be if Avia came out with a 'Digital Avia' (for the sake of giving it a name) that you may see the same LFE issues there.

That said, the folks who make DVE indicated the issues relating to low frequency and the room shape and position of speakers and the position of the listener/microphone - all affecting what reading you get. I feel its sort of like spotting a football - its NOT an exact science from any practical position of a user.

 

[Brian L]

The current issue of WSR has a Q&A from Joe, which does discuss the issues with the LFE test tones.

Not much more info is included beyond what has been posted here, other than he does say that there is a 2 dB difference between VE and DVE (DVE is 2 dB hotter), and that he feels room acoustics are the principle cause of the difference.

Not sure I concur. For giggles and shits, I am going to recalibrate using both VE and DVE. FWIW, I do EQ my sub below 80 Hz (1/2 octave frequency centers), and use an 80 Hz crossover (a couple issues mentioned by Joe). FR is not flat, but is very smooth in the bass region.

When I initially ran DVE, it sounded like someone had turned the sub off. While see how it goes after a "take two".

BGL

 

[Deane Johnson]

other than he does say that there is a 2 dB difference between VE and DVE (DVE is 2 dB hotter), and that he feels room acoustics are the principle cause of the difference

Somehow, this doesn't make sense to me. How can room acoustics make a 2 db difference when the only change is the source DVD?

All in all, this whole situation is very disappointing. When a company puts our a reference standard test DVD, it should indeed be a reference standard. Otherwise, it's worthless.

 

[Brian L]

Dean,

The 2 dB difference mentioned in WSR is in the encoding. The reason for that, if I read his article correctly, is improved measuring methods, and the fact that the tones on DVE are wider in frequency.

Joe is saying that if you measure more, it may be due to a variety of causes, including room acoustics.

As I said, I am not sure that there is not more to it than that, but it is what it is.

I will take another set of readings (VE vs. DVE, and maybe throw in Avia to add to the confusion!), but bottom line, if it does not produce pleasing results (accurate or not), then I won't use if for sub calibration.

And no, I am not one of those that runs his sub 15 dB hot. I may bump it +/- 2dB from reference, depending on content, but thats it.

BGL

 

[Thomas Smailus]

I'll agree. It doesn't make much sense. If the only change is the disk, and the readings are different, you know the difference MUST be a result of what is on the disk.

Now there was some statement about the nature of the LFE data comming off of the two disks being slighly different, correct? It is possible if the spectrum of the signal in the LFE channel is different - the way it interacts with the room and equipment you have configured can be different.

If the 2 disks had exactly the same signal on them and they came out different in a reading - its got to be the signal thats wrong on one of them. Its the case, here, though, that one has a more complete 'across the spectrum' signal on it vs the other disk. Now how that comes into play in the LFE is a little odd, since thats a very band-limited signal anyway, right? I mean its, what, say 10-180Hz or some such thing.



But keep in mind, what are you trying to achieve using these disks? Most want to get a proper balance of the channels. However, do we know what that should sound like? You don't know if any theater you listen to is set up right either -or if your seat in the theater gives you a good soundstage or not. If the one disk is 2db high or low - how important is that in most applications? Use the disks to get into the ballpark and then tweek to YOUR taste. YOu cannot tune it right so that all say 8-12 listening positions in your home theater get an ideal experience anyway.

 

[Robert Anthony]

well, I bought DVE more for the VISUAL calibration, the test patterns and such. The audio section I didn't really need, I fine tuned my set-up a long time ago.

And based on that, DVE was perfect. My TV has almost ZERO geometric errors, 2.5 overscan, it's color, contrast, sharpness and brightness all dialed in perfectly. VERY easy to use, as well.

I can't complain.

 

[Max Leung]

Has anyone used DVE for grayscale calibration? Any issues? Better than AVIA?

 

[Darren Gross]

I was hoping for more step by step geometry and overscan correction calibration tips.

There are simply a few test patterns in those areas with no narration to describe what to change or modify...There's an elementary discussion of geometry and overscanning, but no detail. There are several adjustments in the geometry section (service/dealer menu only, but I have access) which are very hard to fine tune visually and I'm disappointed that it's not dealt with on the disc. What do professional TV installers/calibrators use? I'm tired of all the overscan on an otherwise stellar TV set.


Also the interlace/progressive test pattern desperately needs some narration to allow me to judge whether it looks like its supposed to or not. Again, a simple intro section and a test pattern that tells you way too little...

After listening to all the technical info (my head spinning around and my eyes clouding over after awhile) I made the necessary adjustments and nothing changed- it was set absolutely perfectly with the THX optimizer, ironically...

Should make good use in the surround sound calibration sections, though...

 

[Ted Lee]

apologies if this was already discussed.

i alredy own s&v tuneup, but i just bought a mits 65" rptv.

obviously, i want to ensure i'm getting the best possible pic. will i see enough tests to make the upgrade to dve worthwhile?

thx,

ted

 

[Dave R.]

So, as I understand this, JKP is now stating there is only a +2dB increase to the DVE LFE (limited bandwidth) channel level when compared to the VE mix in their environment.

Based on that, I'm assuming that JKP is backing away from the October recommendation to mix LFE at 80 dB? Which would mean to "fall back" to the instructions on the DVD and set all channels at 75dB with C weighting and slow response on the meter.

Is that the group's consensus?

 

[Bob_Hitson]

Bump...

 

[BRADH]

So I have been using the dve sub setting for a few weeks now and I think its ok 2db lower than the old ve and was wondering what the rest of you think if you have tried it, and if any one with a auto calibrition on there reciever has conpared the two levels>

Brad