Originally Posted by rabident
I think quite a few people put subs on their front wall, but for the sake of argument assume no subs and just a center behind the screen, crossed at 80Hz like you said.
What happens to the center channel's output level between 80hz and 499hz if you just turn up its volume to compensate for the 2.5dB loss above 500Hz ?
For me, concentrating of the frequency response of the two types of screens is an outdated argument in 2013. Any room measurements are likely to reveal LARGE peaks certainly from about 300hz down because of "room gain" regardless of screen used.Therefore, you'll need to EQ most of the spectrum below 300hz any way. Parametric EQ or one of the methods of room correction are readily available either included with the current processors or can be injected via a media server running Jriver. When, the screen required the purchase on an external EQ,then the argument that the woven screen had an advantage might have merit in an anechoic chamber
. I realize that the screen companies are still using what I now consider largely an irrelevant argument, though I note that Screen Excellence includes impulse response, energy time curve, and shroeder response. I'd like to see the results of these types measurements with the vinyl screens. Poorer results are what I would expect.
The primary advantage and disadvantage of the vinyl perforated screens are the increased reflectivity. It's an advantage for video providing a higher gain screen and in my observation a better picture for the most part. It's a huge disadvantage for audio however.
When I was experimenting with different types of screens, one of the things that I wanted to determine was how much an effect on sound quality the lowered screen had on audio even when just listening to stereo. Experimenting with two channel music, it became immediately apparent that vinyl perforated screens when lowered had a type of "boundary effect." The sound was akin to placing the speakers closer to the front wall. First and second room reflection work to smear the sound without some type of absorption at those points. Hanging a large piece of vinyl between two stereo speaker could be described as anti-room treatments because that is the effect I experienced. With un-backed Screen Research fabric, the effect was almost not there. The effect was greater with two of the other woven screens but much much less than with vinyl.
How much of an effect, the type of screen has on audio will also depend on placement and not just the material of the screen. I never tested, but I assumed that woven fiberglass, what Screen Research uses, could have a less detrimental effect on sound than plastic because of the properties of fiberglass. If you mount your speakers on wall and the screen is mounted on top of them, I'm not sure that the reduction of the boundary effect is nearly as great. Logic would seem to suggest it should not be, because of the proximity of the front wall, the reflectivity of sound of the vinyl would be less relevant. I"m not sure it's quite that simple as even when screens are placed on wall, absorption materials are often used. I suspect how freely sound can pass back and forth between the screen materials can impact comb filtering as well.
IMO, both types of screens have advantages and disadvantages. The true audiophile will have an issue with a perforated vinyl screen for audio based upon my experience. Conversely, the true videophile will have issues with the woven screens for picture quality because of screen gain and surface smoothness. Screen Excellence offers the least compromises providing you have a very bright projector. Needing a very bright projector, however is somewhat a compromise.Edited by Bulldogger - 6/29/13 at 12:04pm