# Small Theater acoustics/design



## jimlg (Oct 31, 2009)

I am planning on finishing my basement this summer and plans are to have a media/theater room. I am as much a 2-channel guy as I am a movie watcher, so acoustics are very important. The maximum room size available is 20' by 11'. The ceiling is 7.5 ft tall. My current plan is to incorporate room in room construction as much as possible to limit sound leaking as most of my listening/watching is after kids are in bed. The bedrooms are on the opposite side of the house. 

The sides towards the middle of the basement and rear of the room will have a 2x6 wall to hide the support posts, with separate 2x4 studded walls on either side. I will then place ceiling joists/rafters spaced within the existing 2/10 floor joists to create framing separation there. 

Are there steps I can take now in the framing stage that will help dampen the room? Or is it better to build it like a tank, and then sort out the acoustics later? If I need to choose to fit the budget, the acoustics are more important than the soundproofing.

I guess my main questions would be:

1. What are the steps I should to pursue during construction?
2. Is that room size going to be ok, or should I make it smaller to have a better ratio?
3. is the ceiling trusses within the floor joist a good idea?

Thanks, James


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## danvincent (Jun 22, 2010)

hey James,
the design is pretty good. All you have to do is to check your budget for this project. :wave:


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## SierraMikeBravo (Jul 1, 2007)

Hi James,

Well, you can have both! Good acoustics can be planned as part of a good design. Yes, you should deal with the sound isolation part during the framing stage...but more importantly during the design stage. Plan it all out before you lay the first board. Also, keep in mind if you build the "tank" you will run into issues with it being too warm in the theater, especially if you leave the PJ exposed and if the equipment is in the room; need to have ample HVAC in the room. Remember this though, approach sound isolation from the perspective of keeping noise out. If you do this, it will work in the opposite direction for the most part (those low frequencies can be a real pain to deal with). So, from that perspective, there are a few things I see that could be potential problems in your design. 1. The projector is exposed pumping lots of heat and noise. Consider dealing with that with a hush box. 2. The stairs are right there. Need to isolate those stairs as stairs are attched to the rest of the house transmitting lots of "good vibrations". Also, acoustics deal with many things (seating, subs, speaker positions, etc.). Width is your friend here, so if you can make the theater wider, that would be good thing. You have a good beginning, but you might want to get some more information from the many good threads on here regarding how to design your theater, or you can always have it professionally designed. Best wishes! :sn:


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## sparkymt (May 19, 2010)

SierraMikeBravo - great response. My home theater room will also be along a stairwell and I have to second his opinion to isolate those stairs. The stairwell is an amazing transmitter of sound. Don't overlook it.


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## jimlg (Oct 31, 2009)

Thanks, I had not thought of the stairs as an issue. Do I simply need to frame the theater and stair wall independent of each other to make it work best? Or, will a 2x6 wall be sufficient?

Regarding cooling, as this is in the basement, it rarely ever gets above 65 degrees down there. Will that still be something I need to consider? I do plan to build a hush box. The one in the picture is just what I found on sketch-up.

I agree that a little extra width would be great, but there is a row of support posts where I have the divider wall, so I need to have the wall there. I am meeting with the builder who is going to help me with the framing, and I will see if he has any ideas. I really doubt there is anything to be done as the floor joists are sliced in the middle on a header that rests on those posts.


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## bpape (Sep 14, 2006)

Since you're planning on real room in a room construction, I'd recommend:

- Inner walls built 1/2" short of the joists above. Tie to the joists via PAC International DC-04 clips to minimize structural transmission of sound.

- Use your own joists or trusses sitting on top of the walls and running between the existing joists to completely decouple the ceiling from the structure. This will also provide for minimum headroom loss which may be a concern if doing 2 rows of seating and a riser is involved. 

- Plan your HVAC carefully both from the airflow standpoint and from the isolation standpoint by using flex duct inside MDF isolation boxes. As SMB points out, in a sound tight room, heat can be an issue. Plan on using a good amount of return capacity. Easier to draw hot air out than to try to shove more cold air in and fight the pressure. Let it work for you.

- A cold air return tap into the hush box can help considerably

Depending on the exact location of the support posts, you could potentially extend the wall out a bit and box around the posts with 'columns'. May or may not be a viable option depending on desires for seating, walkway requirements, etc.


Bryan


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## MatrixDweller (Jul 24, 2007)

I guess we'll assume that there won't be any bulkheads running through the room to cover low hanging hvac or plumbing and that the joists run the 11' length of the room. Bpape's recommendation of decoupling the ceiling and walls would be best if that's the case. You'll loose and inch or so of ceiling height, but it will have the best payback in sound proofing. If the joists run the 20' length of the room you would loose a bit more ceiling height as you would need cross bracing/support and thicker joists to keep the ceiling from sagging.


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## sparkymt (May 19, 2010)

bpape said:


> Since you're planning on real room in a room construction, I'd recommend:
> 
> 
> 
> ...



Bryan - How are the joists connected that allow it to be decoupled from the structure? I've heard this is a good way to decouple, but I do not understand how and why it works.

Jon


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## MatrixDweller (Jul 24, 2007)

The box you build inside the room does not touch the floor joists so the vibrations transmitted through the drywall from the home theater do not transfer into the floor joists. Likewise the vibrations from the floor above do not come down into the theater. You would want to stuff the cavity between the floor joists with Roxul or similar to stop resonance and absorb sound between the two rooms.

Another way to do it, if height is at a premium is to use resilient channel or RISC clips.


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## Home Theater Guy (Jul 18, 2009)

Hi James,

I think it's great that you have the opportunity to build a room from scratch. And you're doing very well to consider acoustics this early in the game.

You said you could do a maximum room size of 20' x 11'. Assuming a 7.5' ceiling height, you could go a little smaller on the room size and get excellent modal distribution with a length of 199" and a width of 108". Sure, it's about 41" shorter; but you could use that space as an equipment room with a projector port, which takes care of noise and ventilation problems.

Seriously consider building to these room dimensions. There are no major overlap problems below about 300Hz, which is excellent in any room. With proper subwoofer and speaker placement, it will make a startling difference when you're finished.


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## jimlg (Oct 31, 2009)

Thanks for all the advise guys.

I'll try to answer a few of your questions.

There is no HVAC runs to worry about, and the only plumbing in the way can be moved so no issues there. I have thought about a soffet for lighting, and wiring, and because they are just cool.

I put tape on the room to double check, and figuring wall and ceiling placement, the maximum I have is 88" high, 122" wide and 202" long, so I am closer to what Home Theater Guy suggested. As far as width, slightly narrower is not an issue as it will make the wife's family room a few inches bigger. :sn:

Fortunately, the floor Joists run on the short side, so the room in room will be a snap.

I was at a local Drywall supply and they have green glue at $17.50 for the large tube. Is that a fair price?

Also, I was reading Dr. Geddes paper on small rooms, and he recommends using a large panel similar to the type the Realtraps site also recommends? Is that something I should consider for low frequency dampening? or will triangular bass traps in the corners be sufficient?


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## jimlg (Oct 31, 2009)

One more question before i quit. The hvac is not something I had considered. At 6pmtoday in the basement it was about 70 degrees, and it hit 100 outside today. Will the electronics create that much heat? Or is the necessity based on the room being so sealed?


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## bpape (Sep 14, 2006)

Jon

Your new joists just sit on top of the new walls that you built. There are several ways to attach them. I prefer T brackets.

Bryan


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## Ted White (May 4, 2009)

sparkymt said:


> How are the joists connected that allow it to be decoupled from the structure? I've heard this is a good way to decouple, but I do not understand how and why it works.
> 
> Jon


http://www.soundproofingcompany.com/products/dc-04/rsic_dc04_datasheet/

Image found here.


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## bpape (Sep 14, 2006)

jimlg said:


> One more question before i quit. The hvac is not something I had considered. At 6pmtoday in the basement it was about 70 degrees, and it hit 100 outside today. Will the electronics create that much heat? Or is the necessity based on the room being so sealed?


It's a combination of the sealed room, equipment heat, and people. Trust me, in a sealed room with say 4 people, it will get very warm and stuffy in a hurry without good ventilation. 

Bryan


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## MatrixDweller (Jul 24, 2007)

jimlg said:


> One more question before i quit. The hvac is not something I had considered. At 6pmtoday in the basement it was about 70 degrees, and it hit 100 outside today. Will the electronics create that much heat? Or is the necessity based on the room being so sealed?


A room that size would most likely need two HVAC registers and one return to be truly comfortable. You could get away with one or even no registers, but you definitly need a return vent. The goal is to circulate air in the room. That keeps it warm/cool and fresh. Without any HVAC in the room the air would be stale and since it's in a basement it could present mold/mildew issues. 

When the AC is on you'll get a lot of cool damp air sinking to the lowest levels in your house. If the air doesn't circulate the dampness will collect in the corners and low spots.

Currently without having the walls and a subfloor the concrete surfaces are pretty cool and will lower the temperature of the basement. After you've framed, insulated, put vapor barrier on and drywalled and possibly put down a subfloor and/or carpet that cooling effect will be diminished. The basement will still be cooler however even if fully insulated, because cool air is heavier and will sink to the lowest places in your house. A good recommendation to anyone is to seal up their basement doors with a door sweep to help minimize some of that air migration (saves $$$ too). In the summer you should also close all registers below the top floor.

You projector and electronics will put out some heat too. A projector could double as a hair dryer (no joking). Add in a few warm bodies and the room will get uncomfortable.

If you can afford it, hire an HVAC specialist to properly design your duct work in your whole basement. Typically when a new house is built the builder will cut many corners. One of them is the furnace and is typically only sized to condition the finished living space. Adding many more ducts and returns in your basement can have a detrimental effect on the performance of your furnace/AC if not properly planned. It could reduce the air velocity so that your upstairs is too hot in the summer and too cold in the winter. There are calculations that go into it on how to size the ducts and where to place them. They will also know building codes and _should_ adhere to them.


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## Home Theater Guy (Jul 18, 2009)

jimlg said:


> One more question before i quit. The hvac is not something I had considered. At 6pmtoday in the basement it was about 70 degrees, and it hit 100 outside today. Will the electronics create that much heat? Or is the necessity based on the room being so sealed?


Both the electronics and the people in the room create a lot of heat. Since the room is enclosed and you're likely to stuff several people in there at once, it can get warm very quickly. Home theaters do require more cooling than your average room. I recommend getting a good HVAC installer involved, one who understands how to design quiet systems with enough volume to cool a home theater.



jimlg said:


> Also, I was reading Dr. Geddes paper on small rooms, and he recommends using a large panel similar to the type the Realtraps site also recommends? Is that something I should consider for low frequency dampening? or will triangular bass traps in the corners be sufficient?


I would wait on selecting low-freq acoustic treatments until the room is actually built. Starting with good dimensions is key (I can't stress this enough). The more problems you eliminate here, the fewer you will have to deal with when the room is finished. It's possible that you may not even need specialized low frequency treatments.

Keep in mind that since the ceiling is 88", it changes the other dimensions a bit. 195" x 108" x 88" works really well (I didn't spend too much time on the new dimensions, but you'll get good results with them anyway), with the first problem frequency at about 250Hz. This is about where acoustic absorbers (3" or 4") start to become effective.

Remember that those dimensions are from drywall to drywall and from the ceiling to the finished hard floor. If the ceiling height needs to change further (say to add a floating floor), we'll have to adjust the other dimensions again. Once you get the final ceiling height nailed down we'll be able to nail down the other two dimensions.


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## bpape (Sep 14, 2006)

I would respectvully disagree. No matter what the dimensions are, there are still time domain issues to address in the bottom end that need to be addressed via proper broadband treatments (and/or tuned ones if required). 

A 4" absorber can be pretty effective down to below 100Hz pretty easily. 

The price on the Green Glue is high IMO. That's $210 for a case of 12. Retail on a case is $177. Ted can hook you up. Yes - there will be shipping costs and not sure where you are located but it's likely a wash or cheaper given local sales tax and the over retail pricing the store is charging.

Bryan


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## jimlg (Oct 31, 2009)

Ok, I guess I will need to look at the HVAC situation a bit more. The unit in the house is currently cooling only with baseboard heat and we are looking at replacing that with a heat/cool unit. The ducts are insulation board, and I could easily add another outlet or two for this room. The return may be a bit tricky, but I think it can be done.

The return upstairs is in the bedroom hallway, should that concern me from a sound perspective?



James


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## bpape (Sep 14, 2006)

HVAC ducting is absolutely a noise path. At least it's board instead of tin so it won't ring and amplfy things.

Also, any time you have a penetration of that size in the shell of the room, it is a prime place for sound to get out. Boxing around with MDF and a couple of bends will help with that.

Bryan


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## Home Theater Guy (Jul 18, 2009)

I'm sorry I wasn't specific. I was referring to a velocity absorber (like a simple fiberglas panel) 4" thick placed against the wall. Such absorbers are not very effective below about 300Hz. They provide some attenuation below that, but not to any significant degree. Pressure style absorbers and tuned resonators are more effective here.

More to my point, overlapping room modes below around 250Hz are very difficult to deal with. Acoustic treatments and EQ can help, but they are no replacement for eliminating the overlap with good dimensions in the first place. When someone is building a room from scratch, they have a great opportunity to address acoustic issues from the ground up, which is alway more effective (and less expensive) than trying to fix them after the fact, as I'm sure you'll agree. Once the room is built and furnished with the system up and running, we can specify low-frequency treatment to handle time domain issues as needed.


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## bpape (Sep 14, 2006)

Agreed on avoiding bad overlapping where possible. 

Still disagree on the need for bass control in the time domain and what even std 4" absorbers will do. Here are the coefficients for standard 4" OC703 mounted flat on the wall (A Mount)

0.84 1.24 1.24 1.08 1.00 0.97

0.84 at 125 isn't too shabby.

Bryan


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## Dennis Erskine (May 29, 2010)

> Starting with good dimensions is key (I can't stress this enough). The more problems you eliminate here,


In a small room, fussing over dimensions will gain you more in gray hair than in real postive results.


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## Ted White (May 4, 2009)

Dennis Erskine said:


> In a small room, fussing over dimensions will gain you more in gray hair than in real postive results.


+1


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## SierraMikeBravo (Jul 1, 2007)

I am going to jump in Bryan's camp and also respectfully disagree. Regardless of the room size, you are STILL dealing with a small room. You'll have modes regardless of the dimensions. There are NO magic diemensions. Models are helpful in the respect of where to place your subs and seating, but keep in mind that models are only as good as the amount of assumptions that went into them. Now, there are caveats. If I have a choice of room dimensions that are similar, and one offers more modal support than the other (which is often the bigger one), than I will go with the one with better modal support, but I would never chop off nearly four feet of an already small room. In fact, I usually design the biggest room I can (que Dennis chopping me off at the knees on this one ) and there are many reasons for this including additional modal support, but modal issues should not be the driving force behind calculating the dimensions of a room. Best wishes! :sn:


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## Dennis Erskine (May 29, 2010)

Bigger is always better.


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## Ted White (May 4, 2009)

Tell that to my waistline


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## Home Theater Guy (Jul 18, 2009)

SierraMikeBravo said:


> I am going to jump in Bryan's camp and also respectfully disagree. Regardless of the room size, you are STILL dealing with a small room. You'll have modes regardless of the dimensions. There are NO magic diemensions. Models are helpful in the respect of where to place your subs and seating, but keep in mind that models are only as good as the amount of assumptions that went into them. Now, there are caveats. If I have a choice of room dimensions that are similar, and one offers more modal support than the other (which is often the bigger one), than I will go with the one with better modal support, but I would never chop off nearly four feet of an already small room. In fact, I usually design the biggest room I can (que Dennis chopping me off at the knees on this one ) and there are many reasons for this including additional modal support, but modal issues should not be the driving force behind calculating the dimensions of a room. Best wishes! :sn:


No one is suggesting that there are magic dimensions or that any dimensions can get rid of modes. I certainly never said or implied that. It is possible, however, to minimize the detrimental effect of modes that are too closely spaced, and the smaller the room, the more tight the engineering becomes (in my opinion). I don't even attempt to get rid of modes (as it is impossible), I use them to my advantage by placing speakers and seats to get the smoothest bass response. I think it would a bit irresponsible me as a theater designer to ignore room modes when calculating dimensions (if that is what you mean).

I also prefer larger rooms, but just making a room bigger does not automatically make it better. For example, I would take small rectangular room over a giant cube any day. I have had to deal with cube shaped rooms in the past (where I came in after the fact), and they ain't pretty. You can get good sound but it takes a lot more work in the long run.

To sum up, I just wanted to make sure that the room dimensions were not completely blown over (as no one had mentioned them yet). I take a holistic approach to theater design, where all aspects of the theater are considered. I'm sorry if it looks like I'm getting hung up on one point, but I don't think it's me causing that.

I hope it doesn't look like I'm being defensive now, just stating my position for the record. Thanks for listening, all.


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## Dennis Erskine (May 29, 2010)

Well, I would not suggest one totally ignore the issue. On the other hand, the models are pretty inaccurate, cannot account for simple things like raised seating platforms and soffit, or complex things like wall impedances.

I would also comment that if you're attempting to resolve bass response by seating position, you have some very real challenges. The use of multiple subs and their relative positioning ... well, that's a good practice but if you cannot move the subs after construction, you need better model tools.


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## bpape (Sep 14, 2006)

No problem HTS - just healthy discussion. 

If the room was an extra 5' wide, changing a few inches might be an option. In a narrow room like this, every inch counts. 

IMO, a combination of seating position, speaker postion, and sub position are all key elements to getting the best sound. Seating position is kind of like room dimensions. There isn't a perfect place but you try to stay out of the particularly bad ones.

Bryan


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## jimlg (Oct 31, 2009)

I agree Bryan that in my situation, having the room as wide as possible will be important. 9' wide will make a couch pretty tough to fit, and the extra foot will help a lot. 

I have been thinking about a soffit for lighting and HVAC, but am not sure how it will fit with my ceiling height. Anything more than a six inch soffit will encroach on the door and feel pretty low to a 6'3" guy. I guess I could make it 12-24 inches wide and that would not look too small.

Another issue I need to consider is the location of the house electrical breaker box. It is in the corner of the space where the room will be. I have been told that code will not allow me to cover that with a cabinet or put a closet around it. Should I be concerned about sound leakage there or if I box around it good should it be OK. It is mounted on the concrete block wall. 

I'm hoping to meet the framer this weekend to find out what needs to happen before we can start making sawdust. I am going to have to solve the HVAC issues first, so that may be a delay 

James


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## SierraMikeBravo (Jul 1, 2007)

jimlg said:


> I'm hoping to meet the framer this weekend to find out what needs to happen before we can start making sawdust. James


You need a solid detailed plan. The point is, you should not make decisions on the fly. All the problems should be worked out before you make any sawdust. That way, the building part is super easy...just insert A into B...well maybe not THAT easy. :T Best wishes! :sn:


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## jimlg (Oct 31, 2009)

Yep, that's the plan. I want to get his look and experience on what is going to be the best structurally, and then what I need to have done before we can build. Obviously I need to sort out the HVAC issue, and how were going to route that with the ceiling trusses being embedded in the floor joists, and also how were going to handle the existing window and power panel. 

As far as acoustics, I am satisfied that I will need to do measurement and treatment after the room is built. I have not decided if I am going to do a riser at the rear, and also the soffit is still a possibility. I believe I am going to be bound pretty hard to the 80/20 rule. I am doing this as part of a larger basement finishing project, and the perfection of the theater will take a back seat to the completion of the entire job. Also, I will be satisfied with a nice room and do not have the funds or push to have it absolutely perfect. It will be far better than the storage room/work bench, play room, combo with a white bed sheet screen and a table on table projector mount that I am using now 

You guys have helped a lot.

James


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## tjambro (Jan 16, 2007)

jimlg said:


> I have been thinking about a soffit for lighting and HVAC, but am not sure how it will fit with my ceiling height. Anything more than a six inch soffit will encroach on the door and feel pretty low to a 6'3" guy. I guess I could make it 12-24 inches wide and that would not look too small.


I had the same issues for my basement build and I too am doing a true room within a room. I ended up with soffits that are about 28" wide and about 6" high. Unfortunately, they are directly above the door but they don't feel as low as I thought they would. I'm not 6'3" but if you don't duck now going thru a standard sized door... 

A small portion of that space was divided off and isolated from the HVAC ductboard for can lighting. If you decide to go with cans, you will want to make sure they are isolated from the flex/ductboard because cans are basically just holes with a light bulb in them.


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## bpape (Sep 14, 2006)

And to expand on what Tom said, to allow the soffiting to act as additional isolation for lighting and/or HVAC, the soffits are built AFTER the room is drywalled. That way, any penetrations in the soffit are not actual penetrations in the room shell itself.

Bryan


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## jimlg (Oct 31, 2009)

Well I met with the HVAC and framer contractors today, and have a bit of a plan. I need to get the ceiling insulation down and relocate some plumbing and wiring so the ceiling framing can be put inside the floor joist. Nothing major, but may take some time.

The only thing I'm not sure about is the return for the HVAC. There seems to be only two available options. One would be to run it under the steps, and then outlet it into what is going to be the bathroom. Then there will be a return into the HVAC system in that room. Or, the other option would be to route it under the steps and then go up the inside of that wall and then across the ceiling directly into the HVAC system. The first one is obviously easier, but it seems to me that sound would be an issue.

Thanks ,James


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## jimlg (Oct 31, 2009)

I have a question about an alternative wall material. We are planning to use a wood wall board on the remainder of the basement, and it is a OSB type material with grooves in it to look like vertical board siding. Could I use that as the second layer rather than drywall? It would eliminate the drywall finishing mess and if necessary, I could use the Green Glue between it and the first layer of Drywall.


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## Ted White (May 4, 2009)

If the OSB board is largely a solid panel, then that would work. If the slots are quite deep, and the resulting panel is quite flexible, then your damping will be reduced. Damping is optimal if the stiffness of the two panels being sandwiched is similar.

So Drwyall + drywall is OK. Drywall + OSB is OK. 1" drywall + 1/4" drywall is not so OK.


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## jimlg (Oct 31, 2009)

The product is LP Smartside. It is an exterior material, but that's ok as it will be in the basement, and a little extra moisture/fungus protection will not hurt. It is a vailable in a 7/16 thickness, and the grooves are 1/8 to 1/4 deep.


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## Ted White (May 4, 2009)

That should work fine.


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## jimlg (Oct 31, 2009)

HVAC is going in this week, so we are making progress. The contractor pointed out an easy way to have a direct return and output for the room, so I think that question is answered. Will I want to have a air filter door in the room or should I try to add that further down the duct?

James


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## MatrixDweller (Jul 24, 2007)

Usually the air filter is at the furnace but I know some people put filters on their vents to help keep the duct work a little cleaner. Is this unit a new separate one from the rest of your home?


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## jimlg (Oct 31, 2009)

The HVAC unit is the main house unit and it has a filter in the upstairs opening. We are going to run a flexi-pipe for the return for this room.


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## jimlg (Oct 31, 2009)

Update

The framer is coming in the next two weeks to build out the walls for the basement. The HVAC has been installed, and we will have an output and return in the room.

I have an alternate material question. I work for a roofing contractor and we are removing a clay s-tile roof. The tiles are in great shape, and there are enough left over that I could cover the rear wall of the theater with the clay tile. I think they would add diffusion and I could install them over insulation and leave gaps where the pieces lap at the bottom. Aesthetically, I could paint them a matte black or whatever wall color we chose.

What do you think?

James


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## bpape (Sep 14, 2006)

That's going to be a very hard, non-'giving' type of surface that will be very reflective at a wider range than drywall. It's not going to provide any diffusion. At higher frequencies, it will act as a surface that's not parallel with the opposite wall but only at high frequencies.

Bryan


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## jimlg (Oct 31, 2009)

What type of decoupler is recommended to isolate the wall from the block wall. The framer is concerned about flex if we do not fasten to a wall on at least one side. 

I found this product on Soumndproofing incs site

http://www.soundproofingcompany.com/products/dc-04/

Is that about the best?

James


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## bpape (Sep 14, 2006)

If you build the walls 1/2" short and use DC-04 clips to tie the wall to the joists above, the wall will be plenty sturdy. 

Bryan


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## jimlg (Oct 31, 2009)

So, I would want to attach to the floor joist above, and not the concrete wall?


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## bpape (Sep 14, 2006)

Will take less clips that way and work just fine. They're used for that purpose and will also decouple the wall from the floor above. You can do them to the wall but you need a lot more and really doesn't do much but make the wall stiffer for less control.

Bryan


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## jimlg (Oct 31, 2009)

Ok, so on the walls you would do a 2x3 stud 24" OC with 2 layers 5/8 DW and GG. That would allow the walls to flex a bit. Then on the ceiling, I will have the isolated framing and the same drywall treatment. 

I am going to have a soffet for air and lighting. If I remember, that will be added to the room after the complete walls/ceiling are built.

I will have one door. Is there a good solution using one door, or are double door the best way? The rub on the door is that on a normal evening, those door will be open to the family/living room. My wife is pretty sure she doesn't want to deal with working around an outward opening door. Is a pocket door an option on the outer wall?

Thanks, James


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## bpape (Sep 14, 2006)

Single door is OK as long as it's solid core wood. 

Soffit is done after drywall.

Use 2x4 studs just like a regular wall. The DC-04's allow the wall to move a bit and the clip will provide the flex point and the rest of the wall will flex just like a regular wall - just not transferring the vibrations to the joists above.


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## jimlg (Oct 31, 2009)

Uh-Oh, problems. See pictures


 





 

There are more wires than I thought, and there are cross braces as well. The electric panel is in the corner of the room, so almost all the wires run through there. There is also a large bunch of wire that run throught the joists at the wall and they are about 3" into the room. The wiring is a bit old, and I will be removing all the old baseboard heat wiring so I don't mind moving the wires too bad. But, what is your feelings on the cross braces. The builder thinks I really want them there. I could still use a 2x8 but then I would lose 4" of ceiling room and that would put me under 7'. 

At this point I am wondering I am trying to do too much in the room. Maybe I should just do single framing and two layers of drywall with GG and call it as good as I can do. That would also gain me about 8" in length, and 6 inches in width. 

What do you think?


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## Home Theater Guy (Jul 18, 2009)

Back in the '60s, the NAHB research center conducted some tests on dry lumber and determined that cross-bridging was unnecessary on floors framed with lumber up to and including 2x12s. Many builders just knock them out when they encounter them. I'm not saying to go against your builder, but I think it's worth digging into (check your local codes) to find out if you really need to keep them.

I cannot determine for you how much work you want to put into this room. I will say that it is always easier and less expensive to isolate the room at this stage than later on. If it were my own home, I'm sure I would rather make the effort now than regret not doing it later. But I feel the same way whether it's a home theater, bathroom remodel, or anything else. I would take a step back, look at your overall goals, budget, and resources, get input from your family members, and make a decision from there.


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## jimlg (Oct 31, 2009)

Well, we're making slow progress.

I am at the point where I need to run the wires in the walls, and another option came up. I have a small space under the steps that could be used for an equipment room. The access to it is a bit limited, but it could be a place to put amplification without having to worry about fan noise. Initially I was planning to have a small shelf in the front with sources, and receiver and amplifiers. 

Questions:

1. What are the advantages of having them in another room other than noise and heat, and what wiring other than audio and speaker should I run into there?
2. Will I want my receiver in there as well?
3. In short are the extra complexities in wiring worth the effort?

Future consideration: HTPC

Currently I am planning to have a wall plate at the front with 7.1 channel speaker, and then with hdmi and component to run up to the projector. I also will have a wall plate closer to the back of the room where the couch will be with VGA and RCA audio to hook up my laptop. 

Thanks, James


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## bpape (Sep 14, 2006)

Equipment in room can be done though I prefer it outside and just a IR repeater. Equipment in the front can be very distracting having all the lights while watching a movie IMO.

Bryan


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## MatrixDweller (Jul 24, 2007)

1) Having them in a different room accomplishes a few things
a) Better aesthetics. As you get more and more equipment the front of your room will fill up quickly and the cable mess that comes out the back is harder to manage. 
b) Like you mentioned it can cut down on noise in your listening room if you have fans. It also gives you the ability to cool things better (if needed)and not worry about the added noise.
c) Having a central place in your home to put your equipment and all cable/sat/phone/network hookups is very convenient (and ultra cool).

2) You probably don't want to run big lengths of cable from your prepro/receiver to your amps and other gear. It would be easier to put the receiver in close proximity to everything else.

3) It can make wiring either easier or the same really so I don't thing that should be an issue. What it does mean though is that you'll need a RF remote or an IR repeater so that you can control the components when they are out of sight. That will add at least a couple hundred to your budget.


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