I have a Marantz VP-12S4 projector with about 600 hours left on the lamp, and I'm not happy with its light output when it comes to HD images (I have both Blu-ray and HD DVD players). I'm considering buying the JVC DLA-HD100. Will the change be worth it as far as brightness is concerned? What about replacing the lamp in the Marantz?
I have a 120-inch screen (gain 0.8), and my projector is in my living room at a throw distance of 5.4 meters (17.8 feet), which is also my seating distance. It's been suggested that I change my screen to a 1.3 gain, but I'm concerned I will lose contrast, as my floor, ceiling, and furniture are all white.
Unfortunately, you are facing several problems. Your screen is quite large with low gain—both of these factors lower the peak white level a lot, leading to a dim picture. And your environment is white, the worst possible color for a projection system because it reflects light from the screen back into the room (and back onto the screen), washing out the image. The low-gain screen makes matters even worse, since such screens normally reflect the projected light at a wide angle, hitting those white surfaces with even more light than a higher-gain screen would.
Regarding the projector, you need a flame thrower for a screen that size, especially with such a low gain. I don't think any sub-$10,000 consumer projector can adequately fill that screen with light. I don't think that replacing the lamp in your Marantz will help much. As far as the JVC DLA-HD100 is concerned, UAV and Home Theater reviewer Tom Norton found that it actually puts out less light than the previous-generation DLA-HD1, and it's more expensive than the older model by around $2000, so if you want an LCoS projector, I'd try to find an HD1 (or the identical DLA-RS1) in your case. Even if you do, however, it's not going to put enough light on your current screen in a white room to create a good picture.
If you can up your budget, the Sony VPL-VW200 ($15,000) puts out more light, but perhaps still not enough. The projectiondesign Action! Model 3 1080 ($24,500) has two lamps, so it should be able to fill your screen nicely.
If you're going to stick with a sub-$10,000 projector, I strongly recommend a somewhat smaller screen with 1.3 gain, such as a Stewart Studiotek 130, that is no larger than 96 inches wide (110 inches diagonal) and preferably a bit smaller. On the other hand, assuming your current screen is 120 inches wide (not diagonal), it's just about the right size for your seating distance, so if you get a smaller screen, you'll need to move your seats a bit closer to it to enjoy the same immersive experience.
Another option you might want to consider is an ambient light-rejecting screen, such as the dnp Supernova, Planar Xscreen, or Screen Innovations Black Diamond. These screens provide better contrast than normal screens in rooms with high ambient light. This might make the Marantz or JVC look good even in your environment.
Also, it would make a huge improvement in your viewing experience if the room was not white. Ideally, it should be as dark and neutral as possible—my home theater and UAV's testing lab are both painted dark Munsell gray, a special color of gray with no hue. Of course, such a color scheme normally has a very low wife-acceptance factor, so any dark, neutral color would be fine and a far sight better than white!
Update: Just as I was finishing this blog, I got another note from Helcio in response to my comments, which I had sent to him before posting them here.
I have just bought a Panasonic PT-AE2000U, and I could not be happier! Believe it or not, I didn't even have to replace my 0.8-gain screen—the light output is so incredible that the low gain makes no difference at all. This sucker has outstanding brightness, unbelievable definition, incredible blacks, and all that for less than $3000! I could not believe my eyes when I saw it. I'll just have to watch all my Blu-ray and HD DVD movies all over again.
I'm very glad you found a projector that works in your environment, though I'm quite surprised that the PT-AE2000U has enough light output to do the job. I reviewed the previous-generation AE1000U in The Perfect Vision, and I measured a peak white level of 13fL on a 72-inch-wide Stewart Grayhawk RS G3 screen. I can't imagine that the AE2000U has that much more light output. This certainly compels me to review the AE2000U, which I will do as soon as I can.