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That is interesting and easy. Do you use a splitter for this type of application? Actually 3 of these on the used or wholesale market would be a lot less than a 3 chip DLP and brighter. I wonder would it be better?



Joey
 

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Paul


Yes he also has a G90 stack as well and may possibly submit some pics from that setup also.


Joey


I hope he chimes in to tell us about the picture quality from this stack.
 

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i had a double stack sony g 90 crt.

i sale it (together with the faroudja 5000)when i purchase the dpi blacklight 4000 early this year.
http://gallery.avsforum.com/data/509/23chip.JPG

about the maranz stack.

i own also one vp 12s2 and i get from maranz germany a secound unit to try the stack.

it was suprising easy to use them as a stack.

the picture get more punch because of double light.also colors are better because of more light.

about the g 90 stack.if i have a picture at all there is nothing specially about that.it shows my room(a nice black box) with one pr. on top the other on bottom both in a hush box.
 

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W MAYER,


How do you get the signal (either component feed, or a div feed)into both projectors? Do you use some kind of adaptors that has one input, with two outputs to send same signal to each projector?
 

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Quote:
Originally posted by MRJAZZZ
W MAYER,


How do you get the signal (either component feed, or a div feed)into both projectors? Do you use some kind of adaptors that has one input, with two outputs to send same signal to each projector?
On the same token, how do you align the PJ? Also what kind of signal do you send to each PJ? Is it the same?


Just curious....

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Weren't there a lot of questions floating around a while back about how a double stack DLP system's two color wheels would interact? Do they need to be in sync, out of sync, etc... and how would they in turn affect colors, contrast, brightness.


Looks like we finally have some people who've tried it. Is it just as simple as stacking the two, feeding them the same input from a dual DVI card in an HTPC and not worrying about the color wheels?


Also, as the poster above mentioned, without lens-shift, how do you perfectly align them...?

-Matt
 

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I actually did exactly this with two VP-12S1s with three component cables (using splitters) out of curiousity and...the results of my highly scientific techinical review were: the picture was way too bright (i.e., the colors were all way, way too bright) plus no matter how I tried, there was no way to perfectly align the picture. It was almost like looking at one of those old 3-D movies without the glasses on. Maybe after a few beers it would have looked better...but in a word, it was awful.
 

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Interesting.


Alignment should be achievable quite easily if projectors have lens shift (does Marantz 12S# have?).


About colors synchronization on screen.

It would be interesting to know how the sync between wheel and input signal works exactly in a mono-DLP.

If the wheel has its own rotational controler independent from any external input, sync being made by buffering techniques, then we may hope there is hardly any chance that the wheels of the two projectors are synchronized. Whatever happends on screen, it seems impossible to have any external control.

If the wheel rotation is controlled by input signal, then colors on screen would be sync, which should be avoided. At least to minimize color breaking (aka rainbows).

So, in the later case, we should introduce a small time offset between signal sent to both projectors. How much? 1.33ms or less would be nice, supposing a color wheel speed of 150Hz:

1/150/5=1.33ms

Why to divide by 5? I choosed one fifth of color wheel offset between projectors. 5 will always be prime with 6 or 7 (current color wheel implementations for HD1/HD2/HD2+). So 1.33ms should be more than enough to desynchronize colors on screen (less rainbows), and small enough to not notice the offset. In practice, other smaller offsets may be better. Say 1/150/11=0.6ms (I like prime numbers ;) ).


Conclusion of double stacking mono-DLP (and comparing with 3-DLP):

-no or less rainbows (hope);

-double brightness (for bigger pictures);

-easy alignment;

-no loss of contrast compared to a three-DLP (due to its complex optics);

-cheaper than a three-DLP;

-if one mono-DLP goes to maintenance, you can still enjoy with the other;

-you can decide to have two home theaters if there is no agreement in the family to see the same movie ;)
 

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I must be missing something,we are shown two Marantz s2`s sitting on top of each other-can we see a screenshot comaprison of the picture produced by two as compared to one?

Otherwise its just two Marantz`s sitting on top of each other and proves nothing?/
 

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I had a similar result to suzukino when I tried stacking two Sim2 HT200s. I was getting a color fringing nightmare, that I assumed was the color wheels not synching. I never was able to get it working and watching it gave me a huge headache.
 

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If one were to stack 3 dlps and make sure that each one was displaying a different part of the spectrum but synched you'd probably get a nice enough picture because you'll have all the comonents on the screen at teh same time. Our feeble little minds may well put the picture together well.


Mind you, if you're gong to go to that trouble then you may as well be using a CRT and getting a phenomenal picture to boot.
 

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I would think that the 'color fringing nightmare' was the result of them being perfectly in sync, rather than out-of.


If they were out of sync, you would not see clear flashes of a single color, since there would not usually be a single color on the screen at once. But with double brightness, regular rainbows would probably be much more apparent.


When I played with the ProjectionDesign F1 SXGA in its high brightness mode (3000 lumens), the rainbows were abominably bad (to me, and I am very sensitive to them). Sounds similar to your experience.


It sort of depends, as Car-Rod says, whether the color wheel position is determined by the input signal, where same signal would equate to same wheel position in both PJs. It seems to me that is how DLP would work, but I don't actually know.


BB
 

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Looks like we finally have some people who've tried it. Is it just as simple as stacking the two, feeding them the same input from a dual DVI card in an HTPC and not worrying about the color wheels?


Also, as the poster above mentioned, without lens-shift, how do you perfectly align them...?

-Matt


no color nightmare ,no rainbow at all at least for my 2 units. yes it is very easy to use the stack.i use a dvd test pattern to align them.and this very stable for 3 weeks if nobody touch it.

the maranz have lens shift horizontal.


How do you get the signal (either component feed, or a div feed)into both projectors? Do you use some kind of adaptors that has one input, with two outputs to send same signal to each projector?

i use the vigatec dune f dvi out and a dvi hub to have 2 dvi out.

for hd i use the samsung 165 dvi out and also the dvi hub.


Actually 3 of these on the used or wholesale market would be a lot less than a 3 chip DLP and brighter. I wonder would it be better?

no don't forget its a 3 chip and 3 maranz is still a single chip.

my big one have almost 10 times more light as one single maranz if the maranz is calibrated for good colors and it has a XENON lamp!


no screen shot are made at the time i have both units.



Conclusion of double stacking mono-DLP (and comparing with 3-DLP):

-no or less rainbows (hope);i cant see rainbow with one and also with the stack.

-double brightness (for bigger pictures);yes

-easy alignment;yes

-no loss of contrast compared to a three-DLP (due to its complex optics);

-cheaper than a three-DLP;my big one have 1250:1 the maranz i measured 2350:1 and almost the same for the second one.so cr. is better from the stack.dont forget the maranz have the hd 2 chip with 12 tilt the 3 chip the hd 1 with 10 tilt

-if one mono-DLP goes to maintenance, you can still enjoy with the other;

-you can decide to have two home theaters if there is no agreement in the family to see the same movie .a good point is that you can easaly sale a maranz a 3 chip ????


I must be missing something,we are shown two Marantz s2`s sitting on top of each other-can we see a screenshot comaprison of the picture produced by two as compared to one?

Otherwise its just two Marantz`s sitting on top of each other and proves nothing?

heat belief what you want.i had this stack for more than 3 weeks.i do it only for me to find out if a stack improves the picture and how.
 

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W.Mayer;


Any chance you could post a screenshot? Best would be a comparision between "solo" and "stacked"....


Thanks!

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HEAT,


"Otherwise its just two Marantz`s sitting on top of each other and proves nothing?/"


This is the kind of talk that rubs people the wrong way and gets their tempers up; your comment is bordering on insulting. People are not required to supply visual evidence for everything they say here, which in any case is similar to calling someone on the phone and saying "Here, listen to these great speakers".
 

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Noah, call me later.... I have some great new speakers for you to hear.... Also, I'll show you my new processors super-cool deinterlacing using my 10fps webcam...


:) :) :)
 
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