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Discussion Starter · #1 ·
I have a Sharp 12000 dlp with 92" Stewarts Firehawk screen. I am using an Ayre D-1x DVD with DVI out. Does anyone know if I would benefit from modifying the Ayre with SDI out, feeding it into an Iscan HD DVDO and then DVI to the Sharp? I heard that for a 1 chip machine that it may not make a difference. I would thnk it should help. Any comments appreciated.


Thanks,

Ken
 

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I would assume that the Ayre scaler does a better job at upscaling then the DVDO. Ayre is top notch all the way, so sending a native 720p signal from the Ayre will be better IMO.
 

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I don't think the Ayre DX1 scales to 720p.


If it's DVI board is similar to the one used in the DX-7 the only output is 480p.

But even at 480p PQ should be very very good. :) :) I tried a DX-7 through DVI and it's PQ was better than other players at 720p like the Denon 5900.


However I've read that the Ayre through SDI to the Iscan HD is also very good


I'm sure Charles Hansen can help here, deciding what is the best solution.
 

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Discussion Starter · #4 ·
You are right. The image is 480p from The Ayre. The video board on the D-1x and DX-7 are the same I am happy with the picture but I figured if i can go up to 720p and there is a difference, then why not. Also isnt it a better picture going SDI to the ISCAN then say DVI or component to the ISCAN?


Ken
 

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Hello Ken,


There are a couple of factors that will have an effect on the picture quality:


1) I would assume that the scaler in the i-Scan HD is better than the scaler in the Sharp projector. (Those DVDO guys are really good!) I'm really not sure how much better, and in what ways, and what kind of impact it would have. You would also want to make sure that when using the DVDO scaler that the Sharp's internal scaler is defeated. Otherwise the signal will be scaled twice, which will definitely degrade the picture.


2) The i-Scan HD uses an external switching power supply. Switching power supplies always introduce noise into the system, which can subtly (or not-so-subtly) degrade the picture quality. There are a couple of things you could try to offset this. One would be to use some kind of power line conditioner. However, I would be tempted to go to a surplus electronics store and find someone that likes to build one-of-a-kind projects. I bet they could build you a nice linear (non-switching) power supply for $200 or $300, which would probably make a nice improvement.


The only way to know how much improvement there is to be gained by using the i-Scan HD will be to run the experiment.


As far as connecting the DX-7 to the i-Scan, I would try the DVI connection first since you already have everything you need to try it. Both DVI and SDI are digital connections and offer excellent signal quality. There are two differences betweent them:


-- The DVI is progressive, while the SDI is interlaced. However, both the Ayre DVI board and the i-Scan HD use the Silicon Image SiI504 deinterlacer and should have equally excellent deinterlacing performance.


-- The DVI signal is RGB, while the SDI is YCbCr. Remember that the disc is always YCbCr and the display is alway RGB so there must be a conversion performed somewhere, either in the player or the scaler or the projector.


There is a *very* slight theoretical advantage to performing the conversion in the projector. You can check this with your current equipment, as both the DX-7 and the Sharp can accommodate YCbCr signals across the DVI connection. *If* there is a noticeable improvement when using YCbCr over RGB, and *if* the i-Scan HD can output YCbCr on its DVI output, then you *may* have *very* slightly picture better quality when using SDI.


(This last point depends on how the internal processing is done in the i-Scan. If it is done in YCbCr color space, there is a greater likelihood of some slight visible improvement. If it is done in RGB, then it is much less likely that an SDI connection could improve things, as there will be two additional color space conversions.)


Also, remember that you won't have to "modify" the DX-7 to add SDI. Instead, send the unit back to the factory and we can install the Ayre SDI board (along with a new rear panel). The main advantage of SDI is to allow for a lower system cost, as the SDI board is significantly less expensive than the DVI board.


Have fun!

Charles Hansen
 

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Discussion Starter · #6 ·
Charles,


The external scaler would defeat the projector's scaler. I used at one time a Faroudja NR series with my Sharp and PMDT. It produced 720p and there was definitely more detail. The only problem was that the image from the Faroudja was too soft for me.


By the way, I have the D-1x and not the DX-7. Am I to assume that your comments hold true for the both units?


I am bringing up the sdi out to the dvdo because that seems to be the talk of the town on the dvd forum.


With regards to the power conditioner, I have a Richard Gray, does this suffice?


Ken
 

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I believe that one advantage with the Iscan HD is that you could feed the projector [email protected] for film.


--Darin
 

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Ken -


I'm a little confused on how the Faroudja scaler produced more detail, yet was too soft at the same time. Personally, I agree with Stacey Spears that the Faroudja "detail enhancement" introduces more problems than it solves. In one posting he called it a "video dehancer".


Sorry for the mix-up on the two Ayre players. The SDI board is available for both models.


The DVDO is probably the best scaler currently available, and an amazing bargain to boot. And just like everything else, there are bound to be better units coming down the pike sooner or later.


I haven't tried that setup, but would imagine that a RGPC would improve the picture quality from the DVDO (or any other scaler, for that matter). However, I would imagine that replacing the switching power supply with a linear supply would make even more difference. And of course there is no reason why you couldn't do both.


Darin -


Your point regarding the frame-rate conversion of the i-Scan is a good one. The i-Scan is (to the best of my knowledge) the only scaler currently available that will do a proper frame-rate conversion to avoid the "judder" of 3:2 pull down.


BDavidson -


You also rightly point out that many displays will not accept non-standard signals. These things are so obscure that they are often not well documented in the owner's manuals. It's mostly a matter of firmware, so there may even be running changes since the manuals were printed. Probably the only way to know if it would work would be to try it.


Best regards,

Charles Hansen
 

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Quote:
Originally posted by bdavidson
Will the 12k actually take [email protected]?
Yep. Stacey and I tried it and it passed the judder test. I've also tried this from my PC and it works, but I get some jumps every so often. I think I need to try reclock on there.
Quote:
Do you know if it will take [email protected] also?
I don't think it will take that. I'm not positive, though.


--Darin
 
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