SWithey Home Theater Construction - Page 2

Larry,

Thanks for the compliment on the colors. No decision on the bar stools as of yet. We're still looking for those. However, I do know (based on the limited space I have), the bar stools will not have arms. I think it will be too crowded back there if they had them. Luckily there are LOTS of choices for this type of chair -- so the hunt is on

Also, you nailed it for the eating and friends seating. I never thought about LAN connections. I do have wireless but having a few wired LAN connection back there might prove to be helpful. I might even add a VGA connection so someone could easily plug int their laptop. Damn, now I need to run more cable

Thanks everyone for the vote of confidence on the HT. I wish I could take off a few weeks from work to get this baby knocked out.. but then that would be too easy

I'm planning to venture over to HD in the next few days to pick up some MDF for the columns. This is the part I'm looking forward to. I love working with wood. I'll post some construction "progress" shots for your review (similar to the notorious "Sandman Thread"). Not sure if I can do as good a job as him, but I'll sure try

w8liftr,

Thanks for the kind words. Please let me know when you start yours so I can watch your progress!

The false wall will be covered with 100% GOM material. The panels are just wood frames that are "open" in the center and covered with the material (just as Greg has shown you above -- Thanks Greg). Since GOM is acoustically transparent, the sound will travel through them as if they were not even there. The wall studs will reflect a small amount of sound, but not enough to be concerned with. In fact, they may offer a little diffusion -- which could be a good thing.

Think of this wall as a big curtain hiding "the good stuff" but lets sound penetrate vs. a hard wall that blocks everything

Greg,

I've been meaning to ask you - what size if that corner piece? Is it just something like a 2x2?

Greg,

Thanks for the reply. I think I'll go with the "simple" solution too.

Picked up my MDF and sheetrock at HD yesterday. Cut most of the wood for the columns with the help of YldeSyde/David. I had to bribe him with lunch and a trip to Wally World



- 7 Sheets of 3/4" MDF to make all the columns and front Entertainment Center
- 12 Sheets of 1/2" drywall for left ceiling vault and new rear wall area. I'm only doing single-sheet thickness drywall since the rest of the room is only single-sheet. Fortunately, only one wall actually touches living space (the other (3) are exterior walls). On the one "living space" wall, sound will need to penetrate a enclosed drybar area and an equipment closet (all walls insulated) before reaching another insulated living space wall. It's not perfect but will be fine for my needs.



Because these sheets of MDF are 8' long, we had to come up with a way to support the wood for the cut. A few saw horses and some other helper supports did the trick.



The cutting process is relatively straight forward -- just push and hope you keep the cut straight. Having a friend help you with the cut really makes a HUGE difference. Thanks David!! Of course he wasn't helping me at this moment because he was taking the damn picture



Cutting a long and narrow board required a quick jig to help keep the board and cut straight.




1st pic is 5 of the 7 sheets of 4x8 3.4" MDF cut into (8) 16" wide front panels and (16) 7" deep side panels. With the 2.5" deep side fabric panels I plan to put on the walls, that 7" depth will be reduced visually to 4.5" in the room.

2nd pic is a mock-up of the column in the HT room. Note, I need to cut the side pieces at an angle at the top a bit (to allow it to fit under the ceiling vault) and the some holes for the speaker. That's next on the list

A few more pics of my progress but not much to show. I have not had much time to work this week.


These are the (2) rear columns in raw form. I still have a lot to do with them but this is a start. I have (6) more to build plus the center section of the front entertainment center. I will say, using the brad nailer allowed me to put these thing together very quickly.

v1rtu0s1ty,

Thanks for the support. July will be here before you know it. I've been waiting 2 years to begin mine. Glad I finally got started!!


Brian (bpape),

As always, thanks for your suggestions and help. You continued assistance on this project has proved to be invaluable!

I do plan to put some inputs in the right side column (the one closest to the rear of the room). Since the chairs will be closest to the wall there (about 1'), figured this would be the most unobtrusive place. I intentionally made the column "side width" wide enough to support a single gang box (possibly a double) with the 2.5" thick panels installed. I figured I could stack multiples if needed. The nice part being is the outlets will be hidden from normal view -- keeping with the WAF (I...I mean "clean look") I'm trying to accomplish with this room

BTW -- a phone line in the room? Have you ever heard of cordless phones and wireless Internet ???

Well guys, here is an update on my progress. Columns are coming along. I have (6) of the (8) built. Yldesyde/David came over to the house again yesterday to help me out. Thanks AGAIN David!! Bpape/Bryan is finishing up what I need for accoustics in the room. I'll post his findings once they are completed.

Well, onto the progress pics. I decided to put together a quick "How To Build a Column" guide. My methods may not be the fastest (or best) way but worked well for me.


Step 1: Line up the (2) side pieces up on edge. Try to put the best edge up as that is the one that will butt up against the front piece. Also, note I have a spare sheet of MDF on the garage floor. This creates a very flat surface and makes the final product a lot easier to nail together.



Step 1a: Here is another shot of the sides sitting up on edge and aligned.



Step 2: Lay the top of your column on top of the side pieces. Be careful as you move the side pieces under the top piece for alignment since balance is the key here -- one wrong move and this thing will fall down like a house of cards.



Step 2a: Here is another angle of the front piece sitting on top of the side boards, held together only with gravity.


..
Step 3: I used a 2" brad nail to attach the top to the sides. I spaced the nails about every 3 - 4 inches. Be very careful to keep your brad nailer perfectly aligned with the side boards as those 2 brads have a tendency to shoot out the sides if it is not.

If you look closely, you can see the little brad nails. I chose to use brad nails vs. screws because it would be less work to prep the MDF for the future maple veneer. It also reduced build time substantially. Because the nails went into the edge of the side boards, the MDF will easily split with any substantial side-to-side pressure. Side support braces are needed to ensure column strength (see next pic).



Step 4: Carefully flip the column onto its belly. I used a 2x2 pushed into the corners to get the strength these columns needed. In order to keep the 2x2 tight against the side and front piece for nailing, I created a quick temporary wedge. Again, I used the 2" brad nailer and spaced the brads about 6" apart. I attached the brads on the sides and from the top for extra support.


..
Final: Here is the front of the finished column. It is 8' tall x 16" wide x 6.25" deep and weighs in at 56lbs. That MDF is heavy but the column is very solid. The second pic is the back of the completed column. You can see the 2x2s that I added for extra support.



Ahh, finally --- (6) of the needed (8) columns built for the HT lined up like solders. If you look closely, you will notice the side cutouts for electrical and AV outlets. Because all my walls will be covered with fabric panels, I did not want to break up the clean lines with any outlets. All these outlets are on the column sides and face the rear of the room. The MDF to the right is for the front columns. I will hopefully get to those tonight or tomorrow.

I must take a small "break" from HT construction to build something WAY more important. Does anyone remember the Pinewood Derby? Well, it's now called Derby Days and my daughter is in Y-Princess (formally called Indian Princesses). The race is in a few weeks so I must make a car. It should be fun to build and I'm SURE this car will be painted pink! Still have to come up with a design for the car.. so any ideas would be appreciated (remember this is for a girl). I was considering a Cinderella carriage theme but I think the wind resistance on it will slow it down too much.

Big Worms,

Thanks for the nice comment. I still have a bunch to do but I'm making headway

Bryan,

What a great idea! I see it painted a pearl white. My daughter would love that. Guess it's time for me to pull out the 'old whittling knife and start carving.

Here is the latest...

Room Accoustics
Bpape (Bryan) and I finally finished the room analysis and figured out what type and how much treatment will be going in the room. We're going with a combo of 1 OC703, 1 OC703 FRK, 2 OC703 and 5.5 Cotton. The OC is for the walls and star ceiling and the cotton is for the rear and ceiling bass traps.

NOTE: The FRK is to make sure the room is not too dead by reflecting the higher frequencies. I'll have a detailed drawing of where things will go in the room in the coming weeks.

Construction
I had a small set-back. I decided to put the side surrounds inside the columns (originally, I was planning to expose them and cover them with some nice Maple veneer to match the columns). The issue was I made the decision AFTER I made the (4) MDF side surround columns . It only cost me (3) sheets of ¾ MDF ($60) but the time to re-build them sucked. The silver-lining is it gave me a chance to re-think the column design and I did make a few changes that will work out better. If this is the only mistake I make during the build, I'll be really happy

I also built the front wall columns that will flank the screen. Those were a bit more challenging because of their sheer mass. I'll have more detail on them in a few weeks.

What's Next (The short list)
- Cover up the front window (since the screen will be in front of it)
- Frame out the window to support the screen
- Apply firing strips along the walls to support the columns
- Veneer all the columns
- More to come

Pics
The main reason for absorption in the room is to reduce the RT60 time. The RT60 time is the amount of time (in milliseconds) that is takes sound to decay by 60db. The critical part is to get the decay times to be relatively even after treatment (as opposed to putting up the same amount of absorption in sabines at all frequencies since things like carpet, air, humans, etc. inherently provide some upper mid/high frequency absorption by themselves).

Now this might stir up a mild discussion but bpape and I decided the target point for in my room being 80% HT and 20% music was around .31.


This is my room with (4) chairs, carpet, single drywall and 2 humans. This pics shows that this room would be way out of control if left like this - but it's a starting point.



This pic shows the addition of bass absorbers in the rear corners and above the star ceiling. We're getting close



The last pic shows where I will be with the combo of 1 OC703, 1 OC703 FRK, 2 OC703 and 5.5 Cotton. This looks pretty good.



Here is a pic of all (8) columns built. The first (2) are the rear wall columns. The next (2) are for the front wall columns. The last (4) are the side columns. The (2) shorter ones are the side columns that will house the side surrounds. I'm building those as a two-piece design so I can wrap GOM over the surrounds and have near zero audio obstruction (I'll have more on that once I get that part built).

This may not be of interest to many of you but I wanted to show you what my daughter and I made this past week. She is involved in a group called Y-Guides (formally called Indian Princesses/Guides). Just as the Scouts have the Pinewood Derby, we have "Derby Days".

The car that they use for Y-Guides is about 50% larger than the ones used in Scouts. Not sure why but man do they let you put some weight on these cars. Max weight on the Scout car is 5oz. Max weight on this car is 24oz -- that's 1.5lbs. It is surprisingly heavy.

I shaped the rectangular block of wood into what you see below. My daughter picked all the colors, the stripe design, flames and even the medallion on the rear trunk lid. Okay, okay -- can you guess what her favorite color is? We had a blast building the car together.

Anyway, the race is tomorrow and she is very excited.

...
Side View and Top View



Front View

David,

Well, we won one of the races and lost the other 2 -- but had a great time. I must say that they had some really spectacular cars there. This was not your typical pinewood derby. There was double decker yellow buses, cars with HUGE bugs on top, a "Mystery Machine" from Scooby Doo, and even one that was like a farm with a horse grazing on top. I might need to re-think my "ho hum" idea next year.

Seriously, it was really fun. Our car weighed in at 24oz on the button. They moved it from Bill Bates ranch to the Paradise Ranch right down the street. My daughter was only after the trophy (and a donut)-- once she got that, she was ready to go. I have a 4 year girl old also, so I have a few more opportunities to get more wins under my belt.