A new take on built in room treatments?



....at least a new look.

I think I’ve come up with an interesting experiment I’d like to pursue but want to run this across some more perceptive eyeballs and experienced minds before getting underway.

Imagine this scenario and lend me some thought on it please.

We have a room just under 14ft wide… and over 23 ft long. Closed in on all sides with various door types. Main speakers reside on the short wall. No immediate windows. The ceiling slopes very gently upwards to the center of the room and then down the back half of the room.

See my virtual system pics of ‘Theater at Last for a better perspective.

Now lets build a wall across the 14ft width of the room. Let’s use 2x4 wooden studs for header and footer, and set the studs 24in OC. Doubling the studs on each side wall and at the center opening for whatever doors. Dead in the middle of this wall let’s put a pair of 24x80 bi fold doors. Hang some sheet rock & finish and paint the wall on the ‘seen’ or end user side, and not woory about the back side of it for now. Then, lets put up an on wall, 100 in W x 60 in H DIY movie screen to it, but hinge the screen so it flips up for accessing the space behind it and thru the bi folds!

Then let’s pretty up this partition by applying whatever molding, place a spiffy designer curtin rod, and six floor to ceiling pricey drapery panels on it. . And let’s set this wall 32 in off the perimeter or exterior wall on one end of the room, making it the wall immediately behind the main speakers. The curtains will serve to hide the screen when not in use by merely pulling them too.

In the interim, we’ll use this unused .space we’ve just made for storing boxes of the gear we’ll buy and/or sell later on, so it will remain safe and dry in a temp controlled environment. And reasonably handy.

Now, exactly what can be done with this wall to acoustically treat the room? Remember? We left the back side of this wall unfinished, unfilled, and undrywalled. It’s naked!

My thinking here is to set unfaced 2 in thick by 24 W by 48 H mineral wool panels, or 3 in 705 fiberglass panels, into the rear or unfinished side of this wall…. And to cut into the front of the wall in between the studs and set some sort of screen material… register… or speaker grill like item… maybe cloth covered as ac treatments are covered with thin near see through materials, accordingly to the room esthetic.

Something like a pic frame of sorts would need be made to set into these slot (s)… and the cloth? Covered grills can be any height up to 8ft, and up to 2ft W..

Naturally the absorptive or if better still, diffusive materials placed into the back side of our new wall can be less than 2 ft wide and doesn’t have to fill the entire section of about 8ft H wall.

Or if it is entirely filled, the opening to that section wouldn’t have to be that size either. I could cut away any portion of the finished side of this wall and wonder too, EVEn IF THAT IS NECESSARY, REMEMBERING THE TWIN BI FOLDS SITTING IN THE MIDDLE OF THIS WALL.

They would allow for sound to migrate into and fill that space indirectly, and directly, so any treamtnet being applied could actually be done on the hidden side of that wall! How effective it would be using this secondary path, I’ve no clue… but am guessing sound is stupid and won’t know or prefer an immediate path to absorption or not.

I’m just lost as to which way to proceed here other than to figure this wall can actually contribute a lot to helping out making the room sound better, and keep hidden a fair amount of the parts doing the work.

For ex… I can fill the space between the studs top to bottom and place only a one foot opening of sorts for any of these ‘slots’.

I may later, use this space for relocating my gear out of it's adjacent room location and shorten up some speaker cabling by so doing.

So any thoughts here on what to do, expect, consider, or avoid, would be immense.
blindjim
FWIW, I would prefer to have the speakers backs parallel to the long wall, with absorptive room treatment behind the listener.
It's way too late for that. The walls up and staying up, right where it is at.

Trust me... there are a few reasons why things are where they are. Bedrooms, kitchens, bathrooms, and hallways have to be accessed. I suppose I could have put the speakers on wheels instead of spikes though... well, at least one of them!

Thanks for the thoughts on the room treatments anyhow.
Bamboo... lightweight, fire-resistant, diffractive. Lots of options/colours but looks a bit "tiki".

Ngjockey

Forgive me, but I fail to see the application of the Bamboo in this scenario... mind expanding a bit more.

I'm already tossing around the idea of using wicker/rattan/ loosely woven 'basket like' fixtures almost like African or Asian war Shields but in a more open fashion, to be used as on wall or on mike stands, diffusers.

....but Bamboo? Sorry, but I just don't get it.
You said you wanted diffusive materials. I'm thinking bamboo halfs or slats vertically on the wall. Maybe even cut into patterns if you're ambitious. Even seen it done on ceilings. Along the same lines, there's also decorative molded/embossed 3D panels.

Ngjockey

Sorry... I simply did not get the correlation, as I was focusing initially on filling the spaces between the studs on the rear of that wall with absorptivwe materials. You are right though... difussion is in order too and bamboo would be a nice fit in my room decor.

Good idea... I'd have to find them split, or pre cut. or pre cut and pre glued/formed.

That last item you mentioned, 'molded'... embossed... a link to them/it would be a big help!

Thanks!
Blindjim - the main frequency "amplified" by your room will be 1125/(23x2)= 25Hz. Unfortunately lack of absorption creates standing waves with peak and valleys at different frequencies at the different location. To tame it you'll need at least 4" high density material placed some distance from rear wall. 4" panels are not common and are expensive. Better to concentrate on removing higher bass resonances. To do that you need 2" thick 4'x8' panels of high density fiberglass like John Manville 817 http://www.jm.com/insulation/performance_materials/products/ci9_800series_spin-glas.pdf

814 is more common but has much worse absorption coefficient at the low frequencies - I ended up buying twelve 817s.
I was once in the room that had all spaces between studs filled with 814 or similar Corning material with fabric over it. Amazing acoustics - you can hear voice so clear and pinpoint exact location/person. My panels are in the making - got backboards, fabric glue etc. but am too busy (read lazy) to finish.

Owens Corning might be more common in your area:
http://esh-docdb.fnal.gov/cgi-bin/RetrieveFile?docid=1195&version=1&filename=Owens%20Corning%20700%20series%20fiberglass%20insulation.pdf
+1 GIK Tri-traps - these work great for clarity in lower mid range. Also agree about not deadening the room too much. My preference is a live front end where the speakers are placed with treatments on side walls (especially needed if speakers are close to the side walls) and behind the listener. Corner placed tri-traps are excellent. Fortunately my current room does not need treatment and even bass modes are acceptable but I know how ver bad a square room can be...in some severe cases room modal EQ is the only solution.
Square rooms are beyond correction with passive absorption devices in my experience (perhaps can be better addressed with active room correction?) and I have yet to see a room that did not benefit from proper acoustical treatment. Admittedly, I have no experienced in shadorne's magical utopia room.

Dave 
With a test tone such as found on Test CDs and even Test Records and a SPL level meter, it’s a snap to find ALL locations in the room, including those in the 3 dimensional space, where very high sound pressure exist. By "very high" I mean at least 4 to 6 dB above the average sound pressure in the room. Maybe as much as 8 dB or more (depending on how you define average SPL) which, for those without a calculator handy, is almost 10 times the average SPL in the room.

Fortunately there are many tools at the audiophile’s disposal, including but not limited to echo panels, corner pads and panels, tiny little bowl resonantors, Mpingo discs, Helmholtz resonators, Tube Traps, crystals, Marigo VTS dots, Skyline diffuser. Thus, any shape or size room can be tamed, even square rooms. I might take time, I’m not sayin’ it won’t. 😄 But without a method it's a very uphill battle, dear readers.
@slaw , @ shadorne,   @geoffkait , @ dlcockrum

why are we replying to a thread from 6 years ago ?
I find it  funny when a member comes in and recommends a piece of equipment and the thread is 6 yrs old and chances are the OP has moved on to something else......