The Room with in a Room Project

After 4 years of scheming and a year of experimenting and a month or two of planning. The time has come to build the big room treatment for the home theater / listening room.

The basic plan has always been to build a room with in a room. A new set of walls that will hide the windows (block out light) and acoustically treat the room at the same time. The experiments have not been very WAF friendly, they are in fact downright ugly, but they have really helped the sound. The bass is now tight and the bells ring cleanly.

I attempted to start this the week of Thanksgiving by just modifying the existing DIY treatments, cover them all with fabric and adjust the placements for more coverage and a better doorway between the HT and dinning room. As soon as I started my new dinning room door hit the projector and I was starting to cover up electrical outlets as well. Time to call in the professionals. A friend of mine is an architect that specializes in high dollar home refurbs in upscale neighborhoods in Chicago. Lucky for me the economy is so bad that he has plenty of time to work on a really small project.

Tim came over took all the measurements, we discussed what was to be done, and the things we could not change. The idea of a room within a room sound crazy, but destroying a family room for an acoustically treated HT for a front project does not actually increase the number of people that want to buy your house when that time comes. So walls that can be left up or quickly (and cheaply) removed at sale time was a given. Tim, the architect, thinks I am crazy, and advises against the project as I will never see even one dollar at sale time for this. That's ok this one is strictly for me. Budget for this is about $2,000. (I hope we can stay with in 150%) of that, time will tell.

Plans call for four new walls all made out of lightweight steel 2x4s and ridgid mineral wool bats (6lb/cft) comparable to OC 705. and covered in fabric. Two doors will be made using similar construction one bi-fold to the dinning room and one pocket door to cover the existing exterior door to the back yard. Tim and I will be doing all of the construction ourselves. Time frame have this finished before the ML Summit vs Sanders 10b speaker shoot out set for late January (see separate thread for this).

Pictures to follow.

Wish me luck

The existing room

This is the front wall as the room is today. You can see the Summits, Stage and Descent i. As well as the home made treatments in the corners, and one Mini HF trap from RealTraps behind the Stage. The blue rope light provides some illumination while watching the TV while not affecting the projectors performance. As you can see the new treatments partially overlap the area for the projector. I had to reduce the image size when I got the Summits.

What is the size of the existing room, and what is the size of the new "room within a room" ? Are you going to end up with a much smaller room ?

DIY room traps

These are the my DIY room treatments, I have ten of them scattered around the room. The are constructed out of lightweight steel 2x4s and Roxul 60 rigid mineral wool boards (some are even covered in black burlap). They are 2 foot wide and 8 foot tall x 4 inches thick (the mineral wool boards are 2' x 4' x 2"). I figured the cost of these to be about $60-$70, they take about an hour to build the first one and then about 30 minutes. These don't look to bad and really sound great definitely worth the time and money.

The side wall

This is the side wall with a panel mounted Script i. This one is made from OC 705. Notice the large side windows. This was a reasonably bright family room, before my wife let me have it.

The back wall

This was one of the best sounding experiments. Covering the entire rear wall, including all but 18 inches of that opening to the dining room. And the two rear Script i. pardon the dust, the new construction has started.

Bernard said:

What is the size of the existing room, and what is the size of the new "room within a room" ? Are you going to end up with a much smaller room ?

Click to expand...

The current size is about 10 foot by 14 foot. The new room will be a trapazoid rather than a rectangle. the new dimensions will be about 9 foot across the back wall, eight across the front wall, and 13 long. I am losing about one foot in each way. The new walls will stand about 6 inches in front of the existing ones. I would have liked to bumped the room by about 2 or 3 feet in both directions but I would have had to relocate the stand alone garage and back deck to do that.

Building the prototype corner module, part 1

I wanted to prototype the corner and the bi-fold door before beginning formal construction. Here are the supplies and tools that you need. A supply of lightweight steel, The bottom channel pieces (U shapped, two fitted together to form a box) are 10 feet long. The upright C shaped girders (4) are 8 feet long. Self taping sheet metal screws (you can not buy too many of these). An chop saw with abrasive blade for sawing the steel. Some tin snips for trimming, a good screwdriver and a cordless drill and small bit for pilot holes.

Building the prototype corner module, part 1

Measure and cut the channel pieces to allow for two 45 degree turns to form the corner, distance between the cuts is 2 feet the same width as the rockwool panels (actually the front distance is 3 inches shorter due to the bend the back is a full 2 feet. IMPORTANT: cut the two channels as a single piece this way the cuts line up perfectly.


Then test fit into the corner behind the Summit, again the upper and lower channels are being handled as a single unit.

This is an ambitious project - most with they had a *BIGGER* room.

I'm sure you'll let us know the end result! And if an audiophile buys your house I'm sure you'll see the dollars you put in.

Nice New Years project John , your ears will thank you I'm sure !

Hey Burke,

PM or call me if you need any help with the work. I will also be happy to bring over any gear to your new room when you are done.

Congratulations again on this!

Oh, and one bit of advice - get those Summits covered for the duration of the work. Or better still, out of there! Builders' dust would be doing them no good!

Burke, very interesting project, I'm eager to hear your impressions of the finished product.

Also, will you be able to take some acoustic measurements?

The software is free (REW) and cost of mics and mic preamps are pretty cheap.

I can even lend you one of my spares and ship you off a mic/preamp and cables if you have a laptop so you can tune with the aid of some acoustic measurement tools.

No problem letting you keep them for a month or so.

Cheers,

Some questions about the top side of this effort.

I see your side panels do not go all the way to the ceiling, have you factored in any impact from that?

Also, any celing treatments planned?

JonFo said:

Burke, very interesting project, I'm eager to hear your impressions of the finished product.

Also, will you be able to take some acoustic measurements?

The software is free (REW) and cost of mics and mic preamps are pretty cheap.

I can even lend you one of my spares and ship you off a mic/preamp and cables if you have a laptop so you can tune with the aid of some acoustic measurement tools.

No problem letting you keep them for a month or so.

Cheers,

Click to expand...

I do not have the mics and preamps at this time, althought I have looked into them many times, just never pulled the trigger. I do not have a laptop but do have a computer that is portable enough to move into the media room for a while. It would be interesting to test the room as it is now, (experimental treatments), untreated just before new contruction (no treatments at all), and then finished and compare the results. I will send you a PM, about borrowing you spares.

JonFo said:

Some questions about the top side of this effort.

I see your side panels do not go all the way to the ceiling, have you factored in any impact from that?

Also, any celing treatments planned?

Click to expand...

Yes, the room height is about 8.5 feet so I chose to simplify construction by using prefab panels and studs rather than having to cut each stud (from a 9 foot section) and cut panels to fit, but there is still time to change that decision. A thought was to fit the top with white rope lights for indirect illumination, that would be left on during movies. I did not factor in any acoustic impact of that design, Thankfully the ML speakers do not have a big vertical dispersion.

Destruction day

Had the day off work, so today was destruction day. Time to remove all the speakers, electronics, furniture. Next take down all of the existing treatments, and curtains. (Hey, this rooms is bright without all that junk). Now I just have to pull up the carpet.

The room certainly has its challenges untreated with the large opening, windows and door.

Burke, what is the glorious looking 'white stuff' outside your window ??? would you be so kind and send some of it to Pa !!!!

Tally of currently owned treatments

4 - 2' x 4' x 4" open back Acoustics panels from ATS
1 - HF Mini trap, from Real Traps, Inc
10 - 2' x 8' x 4" DIY acoustic panels