I received my sample of SeymourAV screen material today. It does not have the black backing material. It is cut on the "bias" at about a 15 degree angle to the hole structure, just as advertised on the website. My first impression is that it is much more "open" than I expected. With a "spec" of 5% open area, I expected very little visual transparency.
Originally Posted by SeymourAV
This is done by having the holes as small and closely spaced as possible, while maintaining an openness factor of around five percent
Holding it in my kitchen, with nothing but ambient daylight, it's possible to see right through the fabric. (It's probably too opaque to get Victoria Secret's interested in it as a lingerie material
, but it's certainly more see-thru than I expected.) In fact, it looks to my eye to be a lot more "open" than just 5%. If you look at the size of the holes vs. the size of the area separating the holes, I would guess the open area to be about 25%, maybe a little more than that, (note that I said "guess", as I don't have the ability to actually measure it.)
Just for reference, I can hold the material up in front of my computer monitor and I can still read my text through the screen material. It's dark and it's blurry, but it's still legible. This is much more visual transparency than I would expect from a material that only has 5% of it's surface area "open". The pictures of the Seymour AV logo that Chris posted above are also an example of the visual transparency of this screen material. In the first few pictures, you can distinctly see the logo through the screen material.
I also held it up 6" in front of my current screen, (Da-Lite HCCV). There is enough light passing through the material to show the image behind the sample on the Da-Lite screen; (of course, it's much dimmer than the direct image on the front of the sample, but it's visible nonetheless.) However, it appears to me that significantly more than 5% of the available light is passing through the screen material.
Surprisingly, even with the light loss through the screen material, the image on the front surface of the sample is still *slightly* brighter than the image on the HCCV screen. This makes some sense as the SeymourAV material is rated at 1.16 gain and the HCCV material is 1.1. Also, blacks are just *slightly* less black than on the HCCV, which again makes sense because the HCCV is a gray base, whereas the SeymourAV is a white base material.
I could see no moire'
pattern, but viewing the material from arm's length and holding it about 8" from the Da-Lite screen, the pixel structure of my Sony HS60 seems a little more noticeable on the SeymourAV material, or maybe I should say the image looks more "textured" on the Seymour. However, if I tape the screen sample to the screen, I can't see any more texture on it from my usual seating distance of 12'.
The acoustic transparency is a little harder to judge. I held the sample up in front of the tweeter on my center channel speaker, which is a horn-loaded Klipsch RC-7. From about 2' in front of the speaker and with the screen material 6" to 8" in front of the speaker, I *thought* I could hear a slight attenuation of the tweeter. However, the 8" x 12" sample is too small to make an accurate judgment of this property. Nonetheless, after seeing a sample of this screen material, I am less concerned about acoustic transparency than I am about the light loss and the visual transparency.
So, now I have some more questions:
1. How is the "open" area of the screen calculated? Is an "openness factor" of around five percent the same as 5% open area? Is the light loss through the material 5%? Does the "openness factor" give any indication of how much of the available light is lost through the screen material?
2. How would the black backing affect the light spill-through? Does it soak it up completely so none gets through to the back wall? Without it, will I be able to see the shadows of my speakers through the screen material?
3. Does the black backing deepen the blacks at all?
4. Does the black backing significantly affect the acoustic transparency, especially vis-a-vis the toe-in and off-axis issues discussed by pepar above? Although I plan to place my L/R speakers just outside the screen edges, the off-axis response is still important for any LP off-axis of the CC.
5. The final question I have was raised by a very experienced and knowledgeable AV installer I talked to. Will the screen move at all if there is high level bass output from a speaker behind the screen? How far away do the speakers need to be placed to ensure they don't cause rippling or movement of the screen at 60 to 80 Hz?
Finally, Chris, if you could dig up those measurements, I would be most interested in seeing them. Thanks.