Perforated Screens: stories, tips or tales?

I have the 1/12 octave test results on the DaLite. While I am not at liberty to pass it on, let me suggest I use a Stewart MicroPerf.


One other thought ... the DaLite material is not THX. There are only two possible reasons for this:


1. it wouldn't pass;

2. it was never tested;


There are only two reasons for not testing the material:


1. it wouldn't pass;

2. DaLite didn't think it was important.


Da-Lite is an excellent company with many excellent products. On the other hand, I have the 1/12 octave test results and a Stewart MicroPerf.


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D. Erskine

DEsign Cinema Privee
www.DEsignCinema.com

Imagine what you could do, if you could do all you imagine.

Hi,


I had temporarily a Da-Lite AudioVision. I replaced it because I could see the holes from 15' distance and the pixels of my XGA DLP projector had some kind of nasty interaction with the holes which caused a loss of resolution.

One other problem was that I have reflective surfaces and equipment with displays behind the screen. Sometimes I saw annoying reflections and lights.


What I want to say here is that you should be very careful when deciding for a acoustical transparent screen. There are not only acoustical drawbacks, there are also other things to consider.


Emil


[This message has been edited by Emil Naepflein (edited 12-18-2000).]

I currently have a DaLite Audiovision screen and heard horror stories about sound attenuation, pixel gap moire, and low frequency vibration distortion with full frequency fronts.


I think that the sound is fine, but I have electrostatic speakers which are naturally bright, so I might not notice if there was a slight falloff in high frequencies.


I didn't have any pixel gap moire problems, but I have a D-ILA FPTV and an ISCO 16:9 lens which combines for minimal visible pixel gap getting to the screen.


Even with heavy bass scenes and 8-12" woofers up front I haven't seen any picture problems from a vibrating screen (from any distance).


With my first G1000/ISCO FPTV setup I couldn't see the perforations from 10 feet away, but when I upgraded to a G15 (about twice the brightness) I could see the perforations during bright scenes up to 13' away and had to back up the main seating to 15' away, where they are not visible anymore.


I also had problems with the brighter image passing through the screen and reflecting off the back wall and the speakers metal components.

I had to cover the back wall and shiny bits with black felt to stop the reflections, but it looks fine now.


I will be testing the Stewart Grayhawk perforated screen soon, and will be able to compare both the screen's picture properties and audio quality compared to the DaLite screen.


-Dean.

I have a Stewart micro-perf 130 screen (96x54). With a Sony 10HT projector, I was getting moire effects. Moire was essentially cured by using a Cygnus de-pixelating lens attachment.


Apparently, high resolution fixed panel displays cause this effect with the Stewart micro-perf. Stewart was willing to replace the screen, but I decided to keep it after I tried the Cygnus.


You do have to take care to cover reflective and/or bright things behind the screen. Since my A/V equipment is behind the screen, that took a bit of doing. I also use an IR repeater, though the screen will let most remote IR through.


Acoustically, it is wonderful. Psychoacoustically, it is wonderful to have dialog coming from somewhere near the speaker's mouth.


Claude