[impreza276]

Oh Boy... As I sit here typing this a commercial plane is completing its landing approaching overhead at what seems just a few tens of feet above the house. Welcome to the Opposite House theater build? Why Opposite House Theater? Because this new house is the complete opposite to the Fortress Of Amplitude, and mostly not in a good way. The plan was to buy a modern single family home with the perfect basement space for the ideal theater man cave. Then late 2022 said "hold my beer" and all those plans went straight into the trash along with the current housing market train wreck.

The room dimensions are very favorable at 23' by 13'8" by 9' high. The house was built just a decade ago and is modern and efficient. That's where all the good news ends. The house is a town house. The room is the living room on the main floor above the garage, and next to the kitchen. I can barely hear the neighbors, but that means they will hear me well enough once the subs are firing. There are plenty of windows and a large patio door facing the front of the house, which means the whole neighborhood will be sharing the audio to any loud movies I'm playing. The last thing is that, unlike the Fortress, for resale reasons it would be a bad idea to make structural modifications to the room. Lets see how this plays out..

 

[impreza276]

Scratchpad1

 

[impreza276]

More scratchpad..

 

[Just Baz]

Well that was a total waste of time. Whats next, Are you going to inform us on how you upset the neighbourhood with your loud music

 

[sirjaymz]

Wow... sold the Fortress !? Crazy..

Time for a new build !
Good luck on this one.. I really enjoyed watching the last one you built..
Going to be allot different type of build.

 

[squared80]

Option #1: sell the house and move to a farm with a large outbuilding, then commence build.

 

[impreza276]

Wow... sold the Fortress !? Crazy..

Time for a new build !
Good luck on this one.. I really enjoyed watching the last one you built..
Going to be allot different type of build.

Thanks! That's for sure about it being different. I'm trying to approach it from the the 'glass half full' angle

Option #1: sell the house and move to a farm with a large outbuilding, then commence build.

That was Plan A, which is currently a few hundred thousand out of budget in this area. Though no farm for me - One of the reasons for selling the previous house was that yard maintenance effort was too high. In the new postage stamp sized backyard a 'Roomba' robot lawnmower as already been deployed

 

[impreza276]

One of the first items to come into the theater is this black carpet. The Safavieh 2 inch deep shag rugs made a huge sound treatment difference in the previous theater. Unfortunately Safavieh's black California rug is now a peppered black instead of the old deep black. This rug is from a different brand and is not the same quality - 1.5 inch pile and thinning. To bolster its acoustic properties a half inch thick carpet pad was placed underneath.

Using masking tape to visualize screen sizes. It is true that "Objects Are Closer Than They Appear" in theater room photos - The screen wall is much bigger than it looks here.

When using the temporary TV, it surprisingly felt very comfortable to use size wise and I have some regrets about not settling for a TV setup. With a TV I wouldn't have to worry about blacking out the huge windows in the room. But too late - The new equipment is already here..

 

[sirjaymz]

...The new equipment is already here..

And what do we have here ?

 

[impreza276]

And what do we have here ?

The new equipment needed for the theater is a receiver, projector, and screen.

Receiver
A decently powerful receiver is way overkill for the purposes of this theater. However I've always regretted cheaping out on purchases so just gritted my teeth and got a refurbished Marantz SR7015 from the usual suspects. Maybe in 10 years time I will be able to take advantage of its 8k capability.

Projector
The projector was a tough decision. Not because of a multitude of options, rather, there really is no great option on the market for my requirements - Cheap, 4k, and laser/LED with at least the quality of the BenQ HT3550, and with a touch more brightness. I am so done with bulb replacements. Despite being marketed as a gaming projector, the jury has proclaimed that the BenQ x3000i is a fantastic all round projector apart from having no lens shift and average black levels. I wanted to hold out for the laser equivalent of the HT3550 but word on the street is that it is at least a year away.

Screen
Part of the reason that the BenQ x3000i's blacks are not the best is that it is a very bright projector. What is one way of lowering the brightness? Well, get a bigger screen! I could DIY another spandex screen but decided against it and ordered XY Screen's 150 inch 16:9 format SoundMax 4K. The equipment will probably sit behind the screen so it would be nice to have one that can be easily moved. The 4K material has great ratings, and higher gain and apparent sharpness compared to their 8K material.

As for speakers I still have the KEFs and Volts

 

[squared80]

and ordered XY Screen's 150 inch 16:9 format SoundMax 4K. The equipment will probably sit behind the screen so it would be nice to have one that can be easily moved. The 4K material has great ratings, and higher gain and apparent sharpness compared to their 8K material.

Not going to be regretting not getting a TV once that sucker is up!

 

[impreza276]

The cabinets are out of the way and the wall is clear to appreciate its uninhibited glory. This screen wall is intimidatingly huge! I can say with confidence that if you are judging a screen size from a photo posted in this forum, there is a good chance you are completely and utterly wrong because the scale in this picture does not seem to bear any relation to what is seen in real life.

Now for the hard part of this project - Designing the screen wall. The screen wall will be covered in acoustic treatment. The speakers and most likely the receiver will be behind the screen wall. The plan is to place a decoupled OSB wall against the rear wall and have the acoustic material attached to that. I'm thinking of a false wall in front of the speakers/receiver and two poles from ceiling to ground to attach the screen/false wall to. The challenge is to have them not attached to the floor in any way that will ruin it. Triple black velvet for the false wall. The speakers and receiver have to be easily accessible. I'm not averse to putting some screws into the walls and ceiling but the goal remains keep damage to a minimum. How can I make this all happen?

 

[impreza276]

I'm lost in the weeds researching an acoustic strategy. What worked for the previous theater was a large deep shag rug coverage for the floor and comprehensive absorption on the screen wall. Anthony Grimani's recommendations are the opposite. In his reference guidance example there is no absorption on the screen wall. He also says our ears are accustomed to expecting reflections off the floor so a damped floor sounds unnatural. Generally he recommends 15% absorption and 15% diffusion in the room.

A change to the acoustic plan will be to reduce the coverage of absorption on the screen wall significantly and double up OC703 panels to make them 4 inches deep. Anthony also recommends plenty of absorption on the rear wall though his example shows only diffusion. What to do..

 

[impreza276]

What's the best way to stick velvet fabric to 4x8 OSB boards? I'm thinking either 3M-77 or thinly spread carpet glue. A second opinion would help!

 

[impreza276]

What's the best way to stick velvet fabric to 4x8 OSB boards? I'm thinking either 3M-77 or thinly spread carpet glue. A second opinion would help!

These are panels going on the ceiling so stapling may not be the right choice. The recommendations I am seeing are for a glue named Mod Podge. It's pretty expensive for the quantity. There also are some FRP glues that sound like they may work such as Titebond Greenchoice FRP adhesive

 

[squared80]

What's the best way to stick velvet fabric to 4x8 OSB boards? I'm thinking either 3M-77 or thinly spread carpet glue. A second opinion would help!

That's what I did for the walls and ceiling, and it holds well. I sprayed the OSB and the fabric. But I also stapled it behind.

 

[impreza276]

That's what I did for the walls and ceiling, and it holds well. I sprayed the OSB and the fabric. But I also stapled it behind.

That sounds like the best approach. I'll go ahead and use your method. Thanks!

 

[impreza276]

Here is a new challenge as the triple black velvet makes its way over next week. The plan is to cover two sheets of OSB in the TB velvet and hang them on the ceiling, in order to create a black hole over the screen. The original plan was to cover the OSB in the TBV first then screw the panels into clips/hat channel fixed to the ceiling (creating triple-leaf effect ). For ease of installation and to avoid screw heads showing though the panels, I'm considering other attachment options. There is one example where a version of French cleats was used to secure sound panels to a ceiling. Some form of hooking may be another, though the weight of the panels may be a concern. Ideally there would be some form of decoupling. Any ideas?

 

[impreza276]

The initial contender I was hoping for is a heavy duty version of a keyhole bracket. The problem is finding one with a slot long enough to be secure.

The next contender is adapting a heavy duty door chain guard. This might actually work

 

[impreza276]

I found out I owned four electronic stud finders while hunting for joists in this section all night. None of them worked great. False positives and a four foot span that doesn't seem to have any joist running through it. I dug up this magnetic stud finder this morning and it has already located what should be a screw. Will investigate further this evening