Questions About Building My HT

Hello everyone.  This Winter, I'm going to begin building a HT in my basement.  Even though I've searched through this forum, there are still a lot of questions I have that I haven't found the answers to.  I love DIY projects.  My main concern with this project, is building my HT correctly.  I'm very patient and would much rather take my time with this and build it the right way, than rush through the construction process and have to live with mediocre results.  My plan is to build a good, acoustically solid theater and then, over time, as money permits, fill it with the right electronics to give me a WOW experience. 

So that you know, I have a 20-foot long, by 11 foot wide area to fit the HT into.  Once the walls are built, the finished dimensions will obviously be a little smaller than this.  Because of the "Golden Rule," I realize that building a 20 foot, by 10 foot theater will not offer good acoustics.  Because of that fact, I'm planning on building a media room that's 2 feet deep behind the front wall.  That would allow me to keep all of the media out of sight.  I also have another neat idea about the front wall that I'll cover/ask about when I ask about wall construction.

I figured I'd ask about one topic at a time to make this easier on all of us.  I'm really looking forward to reading what all of you have to say.  I'm really AMPED about this whole project!  


CEILING

My brother and I are the only people living here in this house, so I don't have to be as concerned about noise escaping the HT as some other people would need to be.  Having said that, it would still be nice if either of us could use the HT even late at night without worrying about waking the other person who's asleep 2 floors above on the second floor of the house (where the bedrooms are).  With this goal in mind, I had planned on using isolators between my 5/8" drywall ceiling and floor joists.  It goes without saying, I also plan to use batting in the voids between the joists to prevent any "drum effect."  What I'm wondering is whether it would be advisable to install a second layer of 5/8" drywall on my ceiling to help keep sound from escaping the HT.  Try as I might, I can't find any information telling me if you CAN double-layer 5/8" drywall when making a ceiling that utilizes isolators.

I've read that a smooth, painted ceiling is not ideal for acoustics in a HT.  How do most of you finish your ceilings?  Do you just use some type of textured paint you buy at Lowes?

I've also read in this forum about "risers" that can be used to hide your projector when it's not in use.  Do most of you have your projectors installed so they lower out of a compartment in your ceilings?  Keep in mind that the finished dimensions of my HT will probably be close to 18 feet long, by 10 feet wide, by 7 feet tall.  If the ceiling isn't where most of you have your projectors mounted, where is the best place to mount it?  A custom-built table in front of the seats?  I know that where you mount your projector has a lot to do with what projector you have.  I'm planning on buying a JVC RS1 projector (unless you guys talk me out of it), so what ever you think would be a good way to mount one of those projectors is what I'll do.

Thanks for any help on this guys.  I really do appreciate it!

Welcome Victor.  


Yes you can.  I went with a layer of 1/2 and then 5/8ths over the hat channel that was clipped to isolators.  Just mud and tape the first layer before adding the second.  Depending on budget you may want to use Green Glue between them.  I'm not sure how much benefit you will get since you are already using isolators.




I just textured the drywall after the tape and texture, then used regular paint.


Mine is installed on the ceiling using a universal mount.  You can create a compartment and use a motorized lift, it will just really complicate things.  You have to buy an expensive lift, it will complicate soundproofing, will have to be vented, and you are looking at major rework if you upgrade your projector in a few years to one that needs to be in a different location than the RS1.  I have attached a picture I took during construction that shows the mount.





Good luck with your project, keep us updated!

Thanks for the great input and pictures Adam.  That really clears up how I want to construct my ceiling.  Having covered the ceiling, the next thing I'm wondering about is wall construction. 

WALLS

One of my main goals is to build my HT so that the ONLY source of light I'll see when I'm watching a movie, is the screen.  I don't want to see my front speakers, or media center.  To accomplish this, I was thinking about building my HT in a normal, rectangular-shape.  After all the drywall is up, I'm thinking about then constructing an acoustically-transparent false front wall (with a concave shape) to hide my speakers and media center behind.  I could build framework to attach acoustically-transparent fabric onto, or use acoustically-transparent curtains.  Any feedback on these ideas would be appreciated.

Using curtains seems like the best way to me, but maybe some of you in the know would think otherwise.  By using curtains, it would be really easy to gain access to the speakers and media center, so I see that as a huge plus.

Another way I could accomplish this (but much more labor intensive which I don't mind if there are any benefits) would be to make the real front wall concave (no false wall) and build reliefs into it (drywall) for the speakers and media center.  I could then cover the reliefs where the speakers and media center would be with acoustically-transparent fabric.  This would probably give a much cleaner look which is a plus, but would doing it this way give me better acoustics than using the false wall method?

I'm wide open to input on this guys and am more than interested in seeing what any of you have to say about this.

I've seen the fake walls made out of 2x4's and speakers placed strategically in the openings.  Then all openings are covered with panels covered in speaker grill cloth. Not my theater but this guy uses his false wall to put a LOT of equipment behind it - http://s191.photobucket.com/albums/z127/spinefixr/

I don't think there are any wrong ways.  It depends on your room, your budget and other factors.

I put my side and rear speakers into columns, then wrapped them in fabric.  Here they are pre fabric:



In the front I built a stage with an acoustically transparent screen wall on it, and then mounted an acoustically transparent screen (not shown) to hide the speakers.  Both subs stayed behind the screen wall, but the location in the picture was not their final placement.  The black covering on the right side of the wall is insulshield sound dampening material.  I hadn't done the left side yet.  The back,side walls and ceiling behind the screen wall were covered with it too.  If you didn't want to go with an acoustic screen, you could have cutouts where the red rectangles are and put your L/R speakers there.  I didn't because I would have had sound reflections from the doors on either side on the stage.



I didn't cover my equipment as I put it in the back of the room on an in-wall rack.  There are certain things that you rarely touch like a preamp, amp or reciever, and then things like DVD or Blu-ray players that you need easy access to.  If you are going to cover your gear make sure there is good airflow so it doesn't overheat.

Wow Robert!  That guy is serious!  That's one heck of a set up.  I'm REALLY impressed with your HT too Adam.  That stage looks great (everything else does too)!  One thing I'm left wondering about though, is why so many people install soffits in their HT's?  Do soffits improve the acoustics of a HT?  Since I'm going to have a 7 foot ceiling in my HT, I won't be able to install soffits, but I'm still curious.

Yes.  so do colums if placed correctly.  Even with a low ceiling height you might be able to put a smaller soffit around the edge.  It really depends on the room.  I was fortunate to have a ceiling that was just shy of 10ft in our basement, so I had room for both soffits and a large riser.

Thanks for your compiments.  It took a long time, but it was worth it.  I was finally able to get it almost finished late last year.  Still need to fill the nail holes in the baseboard and tweak the subs a bit.

I just found pictures of your HT after it had been completed in another thread Adam and I have to tell you Buddy.  Your HT is SICK!!!  I hope mine turns out half as good as your did.  Yours is a work of art!  I love it!

What you said about the soffits is good to know.  I was down in the basement measuring again and saw that if I could widen my HT to 14 feet if I didn't mind having soffits in the room.  The soffits would have 6' 4" of clearance from the floor.  If I didn't want soffits, I'd be limited to a width of 11 feet.  I have to admit, the extra 3 feet of width sure would be nice.  You really have me thinking now.

Here is where things get dangerous

Thanks again.  I will be happy if I never have to look at a roll of fabric again....

 Just curious Adam.  What size is your HT?  It looks like it's a pretty large one to me.

Approx 16.5ft wide, and I think approx 23ft long. 

Here are some pictures of my basement.  To spell out how I'm planning on doing this;  The back wall of the theater will be at the end of the basement where the side of the stairs is.  The front wall is obviously going to be where the wall with the window is.  Because of the dimensions of my basement, I have the ability to make my HT follow one of the "Golden Rule" ratios exactly, while using almost every inch of available space in my basement.  If I do follow that "Golden Rule" ratio, my HT will be 18' 3" long.  That would leave me just enough room between the back wall of the HT and the side of the stairs for a media center.  If I designed my layout that way, when you stepped out of the HT door, the media center would be immediately to your left (facing you).  You'd walk right past it every time you entered, or left the HT.

If I don't stick to "Golden Rule" ratios, I could make the back wall of the theater butt up against the side of the stairs.  With just a 1 inch gap between the back wall of the HT and the side of the stairs, that would give me a full 20 feet of floor space inside my HT.  I'd love to hear any input on how any of you would would handle this.  Gain 21 inches of length so you can have a HT that's a full 20 feet long inside, or stick to the "Golden Rule" ratio and lose that 21 inches of room length?  Would such small changes in room size even make an audible difference in acoustics?

If you look at the pictures, you'll see the gray beam that runs the length of my basement.  If I frame up the wall on that side of the HT (right side) so that the top plate of the wall fits up against the joists between that beam and the air duct, my theater could be as wide as 12 feet inside if I wanted to do that.  If I stuck to the "Golden Rule" ratios though, I would need to make the HT 11 foot 4 inches wide.  If I did frame up my right-side wall so that the top plate is between the beam and the duct, I'd obviously have to make a soffit to wrap around the beam.  To keep everything symmetrical, I'd make a soffit on the other side of the room of identical proportions.  From what Adam has taught me, soffits improve room acoustics anyway, so that would be a plus.  Like I said earlier in this thread, it is exactly 7 feet from the floor to the joists overhead.

I'm just looking for feedback on how any of you would handle my HT dimensions.

I'd lay out the dimensions in a floorplan program like Visio or Sketch-up and see how furniture, etc fits in each room.  Very, very few of us have perfect dimensions in our rooms and things work out just fine.

And it is Golden Ratio.  The Golden Rule is a completely different thing.

I can't tell you how much I've learned in the past week about all of this.  After taking tons of measurements and doing a lot of math, it looks like everything I want to do will gel.  I'm really looking forward to starting this project in a few months.  Thanks for all the help guys. 

Good luck.  Keep us posted as it progresses.

Alright guys.  I'm finally done mocking up the layout I want to have in my HT.  Don't say I didn't warn you.  I've included tons of pictures.  I hope you like what you see.  The white part of the room you see is the area behind my false wall where all my front speakers will be.  I'm planning on making that little room behind the false wall 30" deep.


The door on the far side of the room in this pic will lead to my laundry room.  The soffit you see on the same side of the room as the door will hide the I beam that runs the length of my basement.




The long wall without a door that you see in this pic will be against a cinder block wall (1 inch away actually).  This layout will leave 10' 3" of room between the front of the riser and the screen.  I'm planning on an eye distance to the screen of 9'.




Below, you can see the screen.  I'm planning on having a 110" AT screen.  I want to have a funneling effect when you look at the screen.  That's why I've designed the angled walls on both sides of the screen and as you'll see, I designed a ramp to angle up to just below the screen from the front stage.




The big, wedge-shaped columns on this side of the HT will hide the 4" diameter steel poles I have in the basement.  The smaller wedge you see that's butted up against the bottom of the soffit on the right is a side speaker (Definitive Technologies speakers).




Below, you'll see my riser.  The total distance from the top of the riser, to the basement floor is 24."  Because of my low ceiling, I'm not able to place the screen very high (bottom of screen will be 20" above the floor).  That means I'm going to require a tall riser as I found out.  Each step up in elevation is a comfortable 8" (just like normal steps you'd fine in a house).




In this pic, you can see a side speaker on the right, tucked up under a soffit and just to the left of the door is a rear speaker.  That door next to the back speaker will lead to the landing at the bottom of my basement's stairs.

With a 20" tall stage, you can easily put subs in it and not waste that space.  Here's one of many examples.

I really like that idea Robert.  You're full of good ones Buddy.  

I'm confused as to where seating is going.  Are you going to have one fow on the floor, then stairs goin to the top riser where you will have a second row?

One other question regarding the 4"pole(s) you are hiding.  Are they at the front (narrow point) of the column, or at the back (wall side)?

The front row of seats (2 Berkline 45002's with a wedge between them) will be sitting right on the basement floor, so that their backs are 3" in front of the 16" high front part of the riser.  The second row of seats (3 45002 Berklines) will be up on the highest level of the riser.  Their backs will be 9" from the back wall.  This will leave the front row viewer's eyes about 9' from the screen and the back row viewer's eyes will be about 16' from the screen.  The back row of seats will consist of 2 Berkline 45002's put together to form a love seat.  Connected to those 2 seats will be another Berkline 45002, but it will have both armrests. 

There are only 2 steel poles in the room.  They will both be hidden in the columns on the right side of the room, in the narrow (front) portion of the columns.  The I beam above the poles will obviously be hidden in the soffit I'm going to build above the columns.  The soffit and columns on the other side of the room are only there to balance out the room.

Can anyone tell me if my columns would likely help, or hurt the acoustics of my HT?  I was hoping that they would at least act like bass traps, if they didn't also help the overall sound quality of the room.  I'm far from an expert on acoustics, but wouldn't they help reduce echos?

If you put them in the right place they help break up room modes.  In your instance, even if it was in the wrong place you might decide that the aesthetic benefit of hiding the metal post was worth it.  If you have excel here is a great article with a spreadsheet that helps you fine tune the size of your room: http://www.ultimateavmag.com/news/10388/index.html