# Theater in unfinished basement space



## patchesj (Jun 17, 2009)

Current unfinished basement has a "room" that is 14'x19.5'. No windows, opening in side wall for double doors. Floor is concrete. 1 and a half walls are poured concrete. Room is below the dining room and in the middle of the house, away from bedrooms. We would still like to keep it as tight as possible. The downside to this room is the HVAC trunk lines are running across the ceiling, taking up half of the room width. They are 92" at the lowest point, but I think for acoustics we should make the ceiling the same level the whole way across. This "low" ceiling height is a bit of a drawback, but I think it can be a workable space.

Equipment:
Integra 9.9 (pre/pro not decided yet, but leaning this way)
Sony 55ES*2 + 220ES amps
Thiel MCS1 L/C/R + SCS3 surrounds (could go di-pole here if it made sense on the sides)
Panasonic PT-AE2000
Not sure on sub choice yet

Based on my quick calculations I think a 110" wide 2.35:1 screen is appropriate. Looking into SMX 1.1 gain AT, but open to opinions on screen. I would like to have the L/C/Rs behind an AT screen for placement purposes, I don't think I can get proper alignment with that screen taking up so much of the front wall.

For construction: New North wall in front of concrete will be isolated from the joists above and be used to carry the load for the new ceiling joists below the HVAC work. Front theater wall (with screen) will likely be a false wall with plenty of absorption material behind it. All walls/ceiling will be double 5/8 drywall with green glue in the middle filled with insulation. Solid core or exterior type door. Platform will be 2x6 with MDF and insulation. Equipment rack will be under the stairwell on the front wall. Projector will be ceiling mounted (probably near the rear wall of the theater).


I'm looking for suggestions and ways to improve the plan. I like to have all options explored and the best choice made prior to picking up a hammer... I'll try to get some pictures of the raw space posted soon.

Thanks


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## patchesj (Jun 17, 2009)

Note that the "room" dimensions listed there are for the space in front of the false wall and the new 2x4 wall on top. Speaker placement, seating arrangement, is all still up in the air. This was just my first stab at it.

Thanks!


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## tonyvdb (Sep 5, 2007)

Placement of the surround speakers is wrong, The rear ones need to have more space between them (about 4') and you should move the rear seating forward about two feet to allow for better coverage of the rear channel speakers.
Your side surround speakers should be moved up farther so they are closer to the sides of the front row seating. See here for more details.


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## patchesj (Jun 17, 2009)

tonyvdb said:


> Placement of the surround speakers is wrong, The rear ones need to have more space between them (about 4') and you should move the rear seating forward about two feet to allow for better coverage of the rear channel speakers.
> Your side surround speakers should be moved up farther so they are closer to the sides of the front row seating. See here for more details.


I remember seeing that the THX recommendation for rear surrounds was 1-3' apart on the middle of the back wall. I guess a lot of the surround speaker placement depends on my "primary" viewing location, right? I've been going back and forth on middle back row vs front row. I think my rear seating would be just within the max THX recommended distance for that size screen, but the front row is close to optimal. I'm not sure in this situation if di-pole sides would help with the dispersion issue and give a better sound for both rows?

This is my first venture into a decent theater, I'm more of a 2 channel audio guy. I'd like to make sure that I end up with a great music listening room as well, 2 channel or DVD-Audio/BR Audio/etc.


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## bpape (Sep 14, 2006)

I would agree. In a 7.1 setup, you want a bit more space between them.

For the side surrounds, it's a tradeoff. IF they're dipole/bipole, and you're mostly concerned with the front row, then they should be directly to the sides of the front row. IF you want a better balance for both rows, then leave them as is.

From an isolation standpoint, using double doors is going to make that pretty unlikely. 1 large, solid core door is a much better isolation candidate.

Bryan


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## patchesj (Jun 17, 2009)

bpape said:


> I would agree. In a 7.1 setup, you want a bit more space between them.
> 
> For the side surrounds, it's a tradeoff. IF they're dipole/bipole, and you're mostly concerned with the front row, then they should be directly to the sides of the front row. IF you want a better balance for both rows, then leave them as is.
> 
> ...


Moving them seems to be the thing to do, not very difficult at this stage.. :bigsmile:

Right now the door opening is roughed in at 74x90. I can fit anything in there. For the walls that are existing, does it make sense to use isolation clips/channels of some type or would the double drywall sandwich be fine? I'm not as worried about sound migrating out to the other areas of the basement, but that 2x6 wall connects to the floor joists above. I have hardwood upstairs and my fear is that the wall will couple to the 1st floor and create a giant transmission path for the sound.


Thanks


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## patchesj (Jun 17, 2009)

Is there a way to take advantage of the volume of unused space under the stairs, under the platform or at the back in the equipment room for use as a big bass trap?


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## bpape (Sep 14, 2006)

Sound is going to move both ways through all of the structure. If the room outside isn't addressed, any sound going out the doors will get upstairs via that method.

For the structure, if the walls are already hard tied to the structure above, you have a couple of options.

- You can just do Green Glue and double drywall.

- You can use RSIC-1 and hat channel to decouple the drywall and them do the double.

- You can add a 2x2 frame around the perimeter of the room (have to remove drywall) and do your own set of staggered studs. This will not require clips but you still do double drywall. This has the effect of making your bottom and top plates 2x6 instead of 2x4. That way, the room side studs won't be connected to the drywall outside and you also have a deeper cavity for lower resonant frequency.

If you're going to the lengths of your own new joists, I'd probably select option 3.

Bryan


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## patchesj (Jun 17, 2009)

bpape said:


> Sound is going to move both ways through all of the structure. If the room outside isn't addressed, any sound going out the doors will get upstairs via that method.
> 
> For the structure, if the walls are already hard tied to the structure above, you have a couple of options.
> 
> ...


Given that one of the existing walls is already 2x6, can I just stagger 2x4s using the same top/sill plates? Basically have them stick out 1/2 inch past the existing studs? Is there an effective way to decouple the "new" ceiling joists from that wall? Maybe just connect them only to the new studs?


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## tonyvdb (Sep 5, 2007)

patchesj said:


> Given that one of the existing walls is already 2x6, can I just stagger 2x4s using the same top/sill plates? Basically have them stick out 1/2 inch past the existing studs? Is there an effective way to decouple the "new" ceiling joists from that wall? Maybe just connect them only to the new studs?


That 2x6 wall is likely a structural wall so I would be very careful what you change about that wall.


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## bpape (Sep 14, 2006)

You can probably add some studs to the existing 2x6 and have them stick out but they're still going to be tied to the top plate, which is tied to the floor above. Another option is to just use firring perpendicular to the existing studs as a poor-mans type of hat channel decoupling. Not outstanding but much better than direct contact.

If you're doing your own joists lower than the existing ones, then it's all decoupled pretty much anyway. 

Bryan


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## patchesj (Jun 17, 2009)

tonyvdb said:


> That 2x6 wall is likely a structural wall so I would be very careful what you change about that wall.


It is structural, but I think adding additional studs would be OK?


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## patchesj (Jun 17, 2009)

bpape said:


> You can probably add some studs to the existing 2x6 and have them stick out but they're still going to be tied to the top plate, which is tied to the floor above. Another option is to just use firring perpendicular to the existing studs as a poor-mans type of hat channel decoupling. Not outstanding but much better than direct contact.
> 
> If you're doing your own joists lower than the existing ones, then it's all decoupled pretty much anyway.
> 
> Bryan


My other concern with a wall in front of a wall would be the door jamb depth. We would be looking at a minimum of 8", probably closer to 10". Of course that gives me plenty of room to add some absorbtion material on the back of the door.

Any thoughts on wall treatments? I was thinking about using a heavy folded drape type material for at least the 1st 1/3rd of the side walls, maybe the whole way around the room. The thought being that if the appropriate material could be found it might negate the need for absorption panels in those locations.

Thanks


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## tonyvdb (Sep 5, 2007)

As Bryan suggested above yes, adding to the wall will be alright.


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## patchesj (Jun 17, 2009)

So here is a sketch of room/screen dimensions using a "room in room" approach to isolation.


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## bpape (Sep 14, 2006)

I assume those are just supplies (HVAC) in the front. The returns should be in the rear. This is not just for airflow but also to draw any dirt/dust away from the screen instead of toward it.

For treatment, curtains all around is a bad idea. You'll have WAY too much high frequency absorption and not nearly enough in the low end. The rear of the room should be a bit more lively for good surround presentation. The front wall should be dead through the dialog range (200Hz or so). Corners are trapped with very thick absorption. The rear wall can be 2-3" material full coverage with a facing to reflect upper mids and highs.

Bryan


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## patchesj (Jun 17, 2009)

bpape said:


> I assume those are just supplies (HVAC) in the front. The returns should be in the rear. This is not just for airflow but also to draw any dirt/dust away from the screen instead of toward it.
> 
> For treatment, curtains all around is a bad idea. You'll have WAY too much high frequency absorption and not nearly enough in the low end. The rear of the room should be a bit more lively for good surround presentation. The front wall should be dead through the dialog range (200Hz or so). Corners are trapped with very thick absorption. The rear wall can be 2-3" material full coverage with a facing to reflect upper mids and highs.
> 
> Bryan


Those HVAC supplies are actually trunk lines that run the distance of the room from front to back. (i.e. duct work hanging from the existing ceiling.). There is currently a single HVAC supply duct located about midway along the concrete wall, with flex duct.


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## bpape (Sep 14, 2006)

OK. You'll absolutely, positively need to bring a return into the room somehow or it will be unbearably hot in there very quickly. Pay very close attention to any HVAC or all of your isolation work is for nothing. A duct directly in the room in a trunk will allow sound into and out of the entire rest of the house. Bass will go through flex like it's not even there so that duct is essentially just a large hole in the ceiling in terms of bass transmission.

Bryan


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## patchesj (Jun 17, 2009)

bpape said:


> OK. You'll absolutely, positively need to bring a return into the room somehow or it will be unbearably hot in there very quickly. Pay very close attention to any HVAC or all of your isolation work is for nothing. A duct directly in the room in a trunk will allow sound into and out of the entire rest of the house. Bass will go through flex like it's not even there so that duct is essentially just a large hole in the ceiling in terms of bass transmission.
> 
> Bryan


I was planning on running the supply into a diffuser box of some type in the front of the room (I can't stand fiberglass duct board, there has to be a better way to supply air and block noise) and then try to pull the air out at the rear (near the projector...). The entire basement is on an independent HVAC zone (with pneumatic dampers in all of the trunk lines). So even if some sound gets in there it won't have any place to go unless the basement damper and another damper are open at the same time (possible), and the sound would need to travel all the way down the trunk into the plenum, turn around, and travel all the way down the next trunk/duct to a register.

The projector will be the only non-human heat generation in the room. All amps/processor/player/etc will be next door in a closet (with ventilation to the open basement).


Thanks


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## bpape (Sep 14, 2006)

Plan on making your ducts encased in an MDF enclosure. Try for at least 3 bends in it and at least 5' between bends for best results. Even duct board won't do diddly to stop bass. Inside the MDF, use flex.

Even with nothing else, in an airtight room, 3-4 people and a PJ will heat it up in a hurry without sufficient ventilation. General rule of thumb if possible is twice as much return as supply so you're creating a vacuum and helping the air flow out of the room. 

Bryan


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## patchesj (Jun 17, 2009)

bpape said:


> Plan on making your ducts encased in an MDF enclosure. Try for at least 3 bends in it and at least 5' between bends for best results. Even duct board won't do diddly to stop bass. Inside the MDF, use flex.
> 
> Even with nothing else, in an airtight room, 3-4 people and a PJ will heat it up in a hurry without sufficient ventilation. General rule of thumb if possible is twice as much return as supply so you're creating a vacuum and helping the air flow out of the room.
> 
> Bryan


What does the MDF do for the sound, if the flex duct is all going to be on the other side of the double drywall? I can understand the bends in the flex trying to absorb some of the sound as it travels inside the duct.


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## bpape (Sep 14, 2006)

Ah, yes, BUT, the flex itself (where it's coming into the ceiling) is NOT behind double drywall. It's simply a hole. There is no drywall mass at the opening. That hole will allow the bass to go right through the flex and up through the floor above. 

The MDF provides mass to stop sound transmission and acts as a labyrinth to help the sound dissipate and cancel itself before leaving the massive area. 

The bends in the flex will be OK from say 1kHz up but do little to nothing below that without the mass. We want the waves to hit a flat surface and bounce back and cancel. Do this 3 times over 15 feet and it's down quite a few DB.

Bryan


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## patchesj (Jun 17, 2009)

Got it. So the pressure waves are basically just "ignoring" the boundaries of the flex since it lacks mass...


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## bpape (Sep 14, 2006)

Correct. The flex is great as opposed to tin as it absorbs mids and highs and doesn't ring and actually amplify sound but it doesn't have nearly enough mass to do anything for bass.

Bryan


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## patchesj (Jun 17, 2009)

So what type of material/facing do you recommend for bass traps in the corners and to apply along the rear wall? I would purchase ready made traps/panels, but I'm going for more of a built in/hidden look for the treatments.


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## bpape (Sep 14, 2006)

Fiberglass and mineral wool are the most common and cost effective. For bass control and rear wall, look at the coefficients for something that has good bottom end performance but rolls off absorption as you go up in frequency. 

For reflection panels, they don't need to reach as deep but they should be absorptive all the way up.

Bryan


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## patchesj (Jun 17, 2009)

Pictures of the raw space. Pay no attention to the sheet hanging on the wall or the futon... Were very important test/demo tools to gain approval for the project.... Borrowed SD Epson projector from the office and played a few DVDs over the weekend to get buy in from the rest of the household.. :bigsmile:



Looking into room from open area in basement
Looking into room towards "rear" wall
Towards front wall from inside HVAC/Mech room
Again, towards rear of room
From outside room looking at stairwell


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## Ted White (May 4, 2009)

patchesj said:


> It is structural, but I think adding additional studs would be OK?


Adding the new staggered studs to a load bearing wall is fine. This will not reduce any load bearing capacity.

http://www.soundproofingcompany.com/upload/SPC-Staggered-Stud-Wall-Guide.pdf


As Bryan said, ventilation is a big consideration.


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## patchesj (Jun 17, 2009)

Ted White said:


> Adding the new staggered studs to a load bearing wall is fine. This will not reduce any load bearing capacity.
> 
> http://www.soundproofingcompany.com/upload/SPC-Staggered-Stud-Wall-Guide.pdf
> 
> ...


For ventilation, I'm thinking that keeping the air handler for that room independant will help with isolation. Perhaps a 300 to 400 cfm inline fan can be tied to a 12v trigger and pull air from the rest of the basement and dump it in the front of the theater. A "return vent" back by the projector can go to a mdf baffle system and back to the open basement.
_Posted via Mobile Device_


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## bpape (Sep 14, 2006)

That can be done certainly - provided the rest of the basement has enough exchange to keep up with the heat. 

Bryan


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## Ted White (May 4, 2009)

patchesj said:


> For ventilation, I'm thinking that keeping the air handler for that room independant will help with isolation. Perhaps a 300 to 400 cfm inline fan can be tied to a 12v trigger and pull air from the rest of the basement and dump it in the front of the theater. A "return vent" back by the projector can go to a mdf baffle system and back to the open basement.
> _Posted via Mobile Device_


The issues are air volume (CFM) and isolation. Air ducts muct be surrounded by absorption and mass to contain sound. Drywall and fiberglass


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## patchesj (Jun 17, 2009)

The basement is about 2700 sq ft, probably 1800 or so in an open area outside the theater. It is on it's own hvac zone so if we keep that at a reasonable temp, the air exchange into the theater should keep it comfortable.
I need to figure out how much air we would need to move in there. I can't imagine it would be more than 300 cfm. Using an independant fan and duct work would allow me to build an mdf box under the stairs for supply and one in the mechanical room for the return. Should minimize sound transmission to the rest of the basement, and eliminate it from using the other hvac ducts to get upstairs. I think...
_Posted via Mobile Device_


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## Space (Jul 18, 2007)

"Given that one of the existing walls is already 2x6, can I just stagger 2x4s using the same top/sill plates? Basically have them stick out 1/2 inch past the existing studs? Is there an effective way to decouple the "new" ceiling joists from that wall? Maybe just connect them only to the new studs?"

On the load bearing wall in question, wouldn't it benefit you over all to build a separate 2X4 wall that is not connected to any of the existing structure? All the little bit here and little bit there of trying to decouple from the load wall still tie the new wall and the new ceiling right back to it. Especially when you try to attach joists overhead, you will find this an issue with good connections being made as the smaller wall dimensions suggested will not allow proper attachment of the joist.

Nevermind the load bearing part of it, the 2X6 wall has compression blocking that makes another connection >besides< the existing connection that the wood I-beams are already making.

Your concerns that this is going to be a source of transmission are not unfounded, it already is a source being as rigid as it is and doing what it is doing, e.g. supporting most likely another wall directly over head.

It's a straight line to the top of the house


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## Ted White (May 4, 2009)

Building a second wall is better for many reasons if practicality will allow it


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## bpape (Sep 14, 2006)

Absolutely if space considerations will allow it.

Bryan


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## patchesj (Jun 17, 2009)

Yep, I think a second wall is the way I should go. That will isolate all 4 walls and the ceiling from anything else, except the concrete floor.
_Posted via Mobile Device_


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## patchesj (Jun 17, 2009)

Does anyone have information or diagrams that would show how to construct two walls next to each other (room in a room), with a doorway? Which wall do you attach the door frame too? How do you keep the frame and trim from becoming a bridge between walls? I'm going to go with a single 36" door instead of the original french door design. Is an "exterior" door with weather striping the way to go?

Thanks


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## bpape (Sep 14, 2006)

Use a solid core wood door with seals. Attach the door to the inner wall to prevent it from vibrating the outer structure. 

You can use 2 passing 1x4's that overlap but do not touch each other and then caulk the gap. Nobody will ever know it's not attached except you.

Don't drywall either of the 2 inner facing surfaces - only the surfaces that face the theater room and the other room.

Bryan


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## patchesj (Jun 17, 2009)

With the thick wall (I'll have a 2x6 and 2x4 wall), do you use doors with a 10" jamb?


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## bpape (Sep 14, 2006)

No need. Standard door on the inner wall. Just make a plate to fake a jamb around the other one and have it slide around the other one.

Bryan


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## Space (Jul 18, 2007)

patchesj said:


> Does anyone have information or diagrams that would show how to construct two walls next to each other (room in a room), with a doorway? Which wall do you attach the door frame too? How do you keep the frame and trim from becoming a bridge between walls? I'm going to go with a single 36" door instead of the original french door design. Is an "exterior" door with weather striping the way to go?
> 
> Thanks


One door per wall is often recommended to create a soundlock.

This is a vital area to maintain isolation. Doors and windows can be big leaks of sound and require as much attention to detail as anything in the project, often more detail.

Solid core doors require medium to heavy weight type hinges and based on this fact alone, the jamb requirements are considerable.

Plumb framing with 1 inch door jamb material solidly placed against the framing and adequate sized and length screws is a requirement to maintain this door over its anticipated life span. 

A threshold is recommended as well. No door knobs...no holes of any kind in the door really. A pull handle and closure work well but the closure is not a requirement, depending on the weight of the actual door.


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## Ted White (May 4, 2009)

Actually, if you are going to be successful at compressing the door seals you will certainly want a doorknob with standard lockset. Otherwise the door will bounce open. The hole for the doorknob is not a significant flanking path, especially with dual communicating doors.

Look at solid core doors. Generally particleboard or MDF filled, although mineral core is also available. Better to look at a "flush" door slab (no recessed panels that create thin spots).

As Bryan said you can build extension jambs to accomodate the wall depth. You don't need to buy a super deep door jamb.

Sing the top hinge screws through the door jamb into the side 2x4 framing. You'll need to replace the short screws they give you


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## Space (Jul 18, 2007)

"Actually, if you are going to be successful at compressing the door seals you will certainly want a doorknob with standard lockset."

A door closer would be far more effective..

Especially in a double wall configuration, where extreme amounts of effort/cash have been put into keeping sound in and or out. It would be akin to shooting ones self in the hand to use a door knob, certainly worth two bullets if you use a knob on each door of a back-to-back door setup.


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## Ted White (May 4, 2009)

Space said:


> A door closer would be far more effective..


I couldn't disagree more. You need to see the type of pressure a properly sealed door exerts. A positive lock is required.

And you over-estimate the flanking potential of the lockset hole.


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## Space (Jul 18, 2007)

Plus magnetic sealing strips....



A hole will allow airborne sound somewhere to go, I am not sure how flanking fits into that.


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## Ted White (May 4, 2009)

I'm thinking acoustic door, which uses compression seals. You're thinking exterior door, which (sometimes) use magnetic seals. Compression seals are better for acoustics, if there's a choice available.

The bugger is that an exterior door has nice seals, but lightweight, foam-filled slab.

The interior solid core door has the massive door slab, but no seals on the jambs. 

So it's common to get a cheap interior solid core pre-hung, and replace the stops (moulding) with a compression gasket system. The threshold can be ommitted as well. 

Yields a heavy, well sealed door. Go to Lowe's and get 2 and build the airlock.


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## Space (Jul 18, 2007)

Ted White said:


> I'm thinking acoustic door, which uses compression seals. You're thinking exterior door, which (sometimes) use magnetic seals. Compression seals are better for acoustics, if there's a choice available.
> 
> The bugger is that an exterior door has nice seals, but lightweight, foam-filled slab.
> 
> ...





I already mentioned that holes are not good when so much has gone into a build up to this point.

The thinking is that if a man will build a room with the utmost attention to detail then there is nothing left but one place that sound will gain passage, in this case using your reference, it will be the door knob hole...which is no concern because all the other areas have been maintained to the inth degree.

Which usually is a difficult thing to achieve for even the most professional installer.

What you are trying to say, and what you are saying are mixed. 

For a better understanding of what I am thinking of and how it is a benefit to people that attempt diy back-to-back or door installs of any kind in an sound environment where attention to detail is required:
http://www.johnlsayers.com/phpBB2/viewtopic.php?f=2&t=1662&start=0&hilit=doors+and+doorknob


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## patchesj (Jun 17, 2009)

Well, certainly some interesting comments regarding the door. Not being an acoustical engineer, I can only add my "common sense" logic. To me sound is pressure and vibration, so if we are trying to prevent sound leakage (and conversely keep ambient noise out) we need to make the room as air tight as possible (pressure) and isolate interior surfaces from exterior surfaces to prevent transference of the mechanical movements (vibration). Again, not being a professional with access to test equipment, my mind tells me that I'm going to have a larger issue with vibrations across the door slab (lack of isolation and mass) than pressure migration via the door hole. I can see the argument for both problems and agree they will both exist. However, being a home owner and not a studio manager I need to take the most cost effective route as well as applying a bit of aesthetic design. 

I am not sure how well received a double door setup with closers on both vs door knobs would be accepted by the more sane non-audiophile members of the household (and general public) :sarcastic:

Can we agree that in the best case studio design where I would be the only person using the doorway the no knob design is better, but in a "home theater/music room" it might push the edge of acceptable design?

To throw fuel on the fire.... My primary focus on sound isolation is between the theater room and the floor above (and rest of primary living area of the house). The area immediately outside the theater door is probably the least of my worries. That space is about 1000 sq ft of "non-living" area, located under the breakfast room/living room on the 1st floor. There is a work out room that will be attached to the open space as well as a basement bedroom/bathroom with a door about 35 feet away from the theater door.


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## Ted White (May 4, 2009)

Walls for dedicated rooms will typically score an STC 55-60. Common solid core doors will score in the high 20s to low 30s. And they're big holes. So we concern ourselves with doors.

Very massive (very expensive) commercial acoustic doors with proper gaskets can move the door to the high 40s. They have doorknobs.

A simple communicting door system (as previously described) to create an airlock can also hit high 40s, and higher, with better low frequency performance for a fraction of the cost of this commercial door. We presume that they are each hung in a decoupled wall.

So the numbers (acoustic and $$) warrant at least a look at the airlock idea. This will be less of an issue if the sound passing through the single closed door is entering a room with absorption, drywall on all walls and ceiling, etc. Sound will still enter the ceiling joists overhead, so make it as difficult as possible.

Ideally certainly you would not have a doorknob, but the acoustic door world at large hasn't apparently figured out a way to have an automatic door closer supply sufficient pressure to compress the seal bulbs and also allow you push the door back out easily. 

What I mentioned earlier was that a doorknob with metal covers on both sides isn't an open hole. And it has a cross section quite a bit smaller than a single gang outlet, which the NRC has tested to not be significant when closed off.


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## patchesj (Jun 17, 2009)

Ted White said:


> Walls for dedicated rooms will typically score an STC 55-60. Common solid core doors will score in the high 20s to low 30s. And they're big holes. So we concern ourselves with doors.
> 
> Very massive (very expensive) commercial acoustic doors with proper gaskets can move the door to the high 40s. They have doorknobs.
> 
> ...


Do you have any links or pictures of the door knobs you are describing? From an aesthetic view, I would like to keep the "exterior" door and door knob the same style as everything else in the house. The "interior" door doesn't really matter, the theater room is going to look different enough... :yikes:

Currently we have solid core doors with a 2-raised panel design, and lever style handles.


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## Ted White (May 4, 2009)

There may be special knobs available. Seems like a product opportunity. They may also very well have a thin gasket. I am not aware of such devices but presume they exist at an expected high ticket price.

I have one of these specialized doors and have a standard Schlage leverset.


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## patchesj (Jun 17, 2009)

One year later and the "build" thread starts:
http://www.hometheatershack.com/for...struction/29022-bluegrass-basement-build.html


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