I while ago I decided that acoustically transparent screen is the way to go. I wanted to place (and hide) all my speakers behind the screen (rather than below or above it) and have a more cinematic feel to projected image and sound. This would also enable a larger projected image size, as I would be able to utilise the space on each side of the screen (currently used by left and right channel speakers). The screen size can be up to 2.7m wide (9), 16:9 ratio. In doing my research several points came to light. There is only one manufacturer that produces credible and THX certified acoustically transparent screens: Stewart Filmscreen Corp. They apply a micro perforation process to a range of different screen materials with gains from 1 to 2 and above. In my case the choice of material would be most likely FireHawk (gain 1.3). The screen does attenuate high frequencies and requires the use of equalizer to compensate to this (Stewart supplies a dedicated equalizer with each screen). Applying micro perforation doubles the cost of the screen. The quote I got from the UK distributor for a fixed Luxus Deluxe Screenwall model SND123H (16:9) exceeded £6,000. The price alone requires serious rethinking of the whole idea of using the transparent screen. While talking to people that have good general experience in home cinema, the predominant advice was not to do it as the screen placed in front of the speakers would impair the sound quality, and if I am really bend on doing it I should only consider placing the centre speaker(s) behind the screen. The only person to enthusiastically recommends using acoustically transparent screen was X3ELS. His opinion carries the extra weight of a person who has actually implemented such a screen in his own home cinema and has some first hand experience (this is also the only of MicroPerf screen that I am aware). X3ELS implementation is a very good example for transparent screens. The X3ELS cinema room is in the former garage that by nature is a long and narrow space. Using the transparent screen not only achieves exact positioning of sounds behind the objects on the screen but also maximises the screen size, as the screen can now take the whole width of the room. X3ELS uses Stewart Lexus Deluxe Screenwall model SND092H with MicroPerf Studiotek 130 material. Listening to the music material I cannot honestly detect any negative influence the screen has on the sound stage, precision or tonal balance. The screen is permanently fixed, so direct comparison with screen removed was not possible. Speakers are active design, Genelec HT210, positioned in level with screens centre line, approx 0.5m behind the screen with left and right channels pointing slightly inwards. The screen perforations are visible on very bright images from the distance of up to 2m. Being transparent to sound also means that this type of screen is effectively leaking the light, i.e. not all light reaching the screen is reflected back. Micro perforations reduce the effective screen gain by approx 10% and require the space behind the screen to be constructed from non-reflective material in order to prevent the leaked light from coming back. In X3LES case the wall behind the screen is covered with light absorbing black cloth. Having recently seen Uncle Erics home cinema and now X3ELS, there are a number of parallels. Uncle Erics space is slightly wider. While Eric prefers his equipment to be visible (speakers, sub, most of the cabling), X3ELS space is completely custom decorated with all the speakers hidden. From interior design perspective I prefer the later implementation. Eric uses pull down screen with left and right speakers are positioned on the lower side of the screen and the centre speaker below it. However, most of the rest is almost identical: Both are garage conversions Both use air conditions Both use Stewart Studiotek 130 screen material, size aprox. the same. Both use CRT projector (X3ELS 9, Eric 8" tubes corrected) with HDLeeza, SDI moded DVD player and High Def D-VHS tape machine. Both use active speakers (Eric uses M&K actives and Velodyne sub) with approx 300W per channel. Both have noise coming from the ceiling mounted projector and some noise from HDLeezas fans. Both use Lexicon MC-12 as A/V processor. Both rooms are acoustically treated. Both rooms have black walls Both rooms have Lutron type light control. Both have excellent picture and sound performance. So, in conclusion has X3ELS sacrificed sound quality by placing acoustically transparent screen in from of the speaker? If he has, it is certainly not an obvious deterioration and probably amply offset with the benefits of such a set-up. I would appreciate the view of the other members with experience with acoustically transparent screens. I am of course very grateful to both X3ELS and Uncle Eric for letting me in on the secrets of their home cinemas.