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433K views 1K replies 153 participants last post by  Reddig 
#1 ·

Updated (index added, original post follows):

Project: DIY HT, approx 15'x26'x10' in basement dug under existing house, IB sub, absorption/diffusion acoustic design, motorized hidden entrance, star ceiling, room within room construction, CIH curved screen, three rows.

Current Status:









Enjoying the theater and still working on the entrance


The starting point (a distant memory):


Thread Index:

1. Basement dig! start / complete

2. Adjacent Garage Remodel: start / complete

3. Framing: start / complete

4. HVAC

5. Skinning the room with OSB

6. Drywall: start / complete

7. IB Sub: start / complete

8. Riser

9. Stage

10. Soffits

11. Star Ceiling: start / complete

12. Design Details & Color

13. Acoustic Treatment: Front / Sides

14. QRD Diffusor Panels: start / complete

15. Quiet Extraction Fan

16. Hardwood Trim: Soffits start Soffits complete

17. Soffit lights: start

18. Carpet & hardwood Floor

19. Seats are in!

20. Walnut wall trim

21. Triggered Outlets

22. 2.4:1 Curved Screen/Masking start / completed (separate thread )

23. Columns start finish

24. Hushbox and A-lens build calibration

25. Media Library

26. Backlight Poster Boxes

Gear:

Subs: Front: DIY IB design with 4x18" Fi drivers

         Rear: 2x Klipsch KW120-THX

Speakers: Klipsch THX Ultra 2 (wired for 11.2 with 9.2 active)

Amps: 2x Berhinger EP4000 (IB sub/rear sub/buttkicker)

         1x Outlaw Model 7700 (7 channel)

         1x Outlaw Model 7500 (5 channels)

Pre/Pro: Integra DHC-80.1

Sub EQ: Berhinger DCX2496 (for 3 channel sub EQ)

Source Player: Oppo BDP-83

Projector: JVC RS40 / Prismasonic HD-6000R cylindrical anamorphic lens

Screen: DIY 130" CIH (2.4:1) w/ automated masking

Media Server: Dune Smart H1

Media Vault: QNAP TS-859+ (16Tb)

Other: Sonos wireless music distribution

          ButtKicker LFE

          Google ChromeCast

UPS: APC J15 (AV equipment)

       APC Smart-UPS (NAS, network)

Rack: Middle Atlantic sliding rack with custom faceplates

  

===================== Original Post =====================


Hi All,


So my dedicated home theater tale begins and I've no idea when it's going to end...


First a thanks for the fantastic goldmine of collective expertise on this forum and the wealth of inspiration. It's been nearly 10 years since the HT bug infected me, about 1 year of reading this forum and thus far about 8 weeks of construction.

The Details:

Approx 30' x 15'4" x 10' space created by converting a under house crawl space into a basement.

Emphasis on acoustic isolation: built as a room within a room, independent ceiling joists, isolated subfloor, DD or TD & GG, communicating door entry, etc

Approx 11' curved CIH AT screen, stage, raised seating

Two rows of three chairs and bar seating at the rear

"Sealed Box" construction - soffits, electrical, etc will all be run inside of the drywall shell

Named "The Old Vic"


I think the most unusual aspect is the starting point. I don't live in the mid-west where everybody has huge basements yet I really wanted an isolated space (well actually the WAF mandated it ;-). So I came up with the idea of excavating out one of my crawl space areas under the house and retrofitting a basement! I'm doing just about all the work myself except for the excavation... I know when I'm beat.


Here is the design so far. It does not show any acoustic treatment/basetraps although these are planned but rather concentrates on the use of space and audio isolation from the rest of the house. I'm curious to hear people's thoughts...

The theater layout:



Floor & Ceiling Construction:
 
 
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14
#3 ·
Job #1 - Clearing pipes/wires/ductwork from Theater space:





Job #2 - Water Heater / HVAC relocation in adjacent crawl space:






Job #3 - Garage Subpanel and new stairs to theater. I have 4 dedicated 20A circuits and 1 15A circuit. Is that enough?
 
#8 ·

Quote:
Originally Posted by BIGmouthinDC /forum/post/15745726


What is holding that mass of concrete up? It makes me nervous just looking at it.

It makes me even more nervous living over it
I have confidence in the team performing this work. The ground is very solid and they are using a line of "pipe-jacks" to hold up the existing foundation whilst they create a new one underneath. Still, I'll be happy when the concrete is 100% done ... it's very close now.
 
#11 ·

Quote:
Originally Posted by dc_pilgrim /forum/post/15746208


What is the acoustic foam in the floor? I have never seen that.


Did you consider acoustikmat which is occasionally recommended here by the guru's?


Awesome build.


Did you consider adding a half bath?

Half bath? Is that a sarcastic comment that you expect my theater to fill with water



The floor foam I have I bought from a friend who remodeled his apartment using QuietWood. The foam is what they sell for floating a floor. It doesn't have much mass but will at least decouple the floor. Well that's the theory. I'll check out acoustikmat since I'm still a couple of weeks away from the starting the interior framing.
 
#12 ·

Quote:
Originally Posted by W00lly /forum/post/15746436


This will be pretty sweet when its all done I wish I would have had that extra 6' for a bar setup. my room is 14'.4 x 24' and I love my big screen I know you will too

Thanks, I'm really excited about a big CIH setup. I was reading your build just the other day -- you don't need bar seating, you have a fabulous bar outside the theater!
 
#13 ·
Any build that uses a mini bobcat definately gets instant wow factor, very cool. Your project looks great. I also question the layers you have for the flooring though. Do you think you need the dricore with the other 2 layers above. I suppose you want the 1/4 inch air gap but from what I've seen on Holmes on Homes he attaches foam directly to the cement floor. What ever you do, good luck. Nice work so far.
 
#14 ·

Quote:
Originally Posted by Moggie /forum/post/15745877


It makes me even more nervous living over it
I have confidence in the team performing this work. The ground is very solid and they are using a line of "pipe-jacks" to hold up the existing foundation whilst they create a new one underneath. Still, I'll be happy when the concrete is 100% done ... it's very close now.


- Paul

I didn't know about this technique.... interesting. I would feel weird walking around above that!
 
#15 ·

Quote:
Originally Posted by oman321 /forum/post/15746911


Any build that uses a mini bobcat definately gets instant wow factor, very cool. Your project looks great. I also question the layers you have for the flooring though. Do you think you need the dricore with the other 2 layers above. I suppose you want the 1/4 inch air gap but from what I've seen on Holmes on Homes he attaches foam directly to the cement floor. What ever you do, good luck. Nice work so far.

Well I'm no expert, just reading, learning and applying some common sense. I started another thread http://www.avsforum.com/avs-vb/showthread.php?t=1116502 about isolation and Dennis Erskine asked about the floor so I thought I'd start this construction thread to get some advice. In my situation I need to be careful about moisture. I've already identified a few problem areas that can be addressed with external drainage and fixing a badly designed roof run off. Still, I'm being cautious and assuming that some moisture will make it's way into the basement. The dricore idea was simply to allow the floor to breath. I could have built directly on that but in an attempt to isolate the room I added the floating false floor. The choice of foam was simply that I got it for free and I *assume* it will do the job -- its called QuietFoam from Quiet Solutions. But, if wrong, I'm hoping the forum experts will set me straight.
 
#17 ·
Moggie,


The foam is a standard 3/8" closed cell cross linked polyethylene. It's 3/8" packing foam, but acoustically tested in a floor assembly.


You are looking to acoustically isolate the floor or is the foam for cushion?
 
#19 ·
Hey ted, Im waiting for your responce. My thought is why he would worry about sound transfer through a concrete floor? Seems to me a 4 inch concrete floor is 10 times more sound proof than 10 layers of sheetrock/GG. Thanx to you and John in minneapolis for all your knowledge. Chris
 
#20 ·

Quote:
Originally Posted by mndentguy /forum/post/15750110


My thought is why he would worry about sound transfer through a concrete floor? Seems to me a 4 inch concrete floor is 10 times more sound proof than 10 layers of sheetrock/GG. Thanx to you and John in minneapolis for all your knowledge. Chris


While concrete is good at providing mass once it starts vibrating (impact) it is a pretty good conductor of sound. Ever been in a building when they are using a jackhammer to break up some concrete? you can hear it several floors away. keeping vibrations from the concrete is a good strategy, pouring the concrete floor with gaps to adjoining foundation elements could also help. I've seen construction where they used rubber gaskets to isolate one floor slab from another.
 
#22 ·
The 3/8 inch foam will not provide sound isolation. It will get compressed a little, and therefore provide some spring effect to create resonance. But the resonant frequency will be high. It needs to be very low, below the lowest frequency you want to isolate.


- Terry
 
#23 ·

Quote:
Originally Posted by Terry Montlick /forum/post/15751722


The 3/8 inch foam will not provide sound isolation. It will get compressed a little, and therefore provide some spring effect to create resonance. But the resonant frequency will be high. It needs to be very low, below the lowest frequency you want to isolate.


- Terry

And that's not going to happen without an air gap and a lot of decoupled mass on the raised floor. Tall order for floors without sacrificing height.
 
#24 ·
In that case would the experts say Moggie should either do the dricore or do the delta and t&g and forgo the foam?
 
#25 ·
He already owns the foam, it can't hurt, so what the heck
 
#26 ·
Thanks for the feedback. I think the consensus is that because this is the only room at this grade (other than the garage) and there is a lot of concrete and mass and distance to the rest of the house it is futile trying to improve the isolation of the floor since it will be good enough in a HT.

Quote:
Originally Posted by BIGmouthinDC /forum/post/15751598


While concrete is good at providing mass once it starts vibrating (impact) it is a pretty good conductor of sound. Ever been in a building when they are using a jackhammer to break up some concrete? you can hear it several floors away. keeping vibrations from the concrete is a good strategy, pouring the concrete floor with gaps to adjoining foundation elements could also help. I've seen construction where they used rubber gaskets to isolate one floor slab from another.

Funny you should mention this. The jackhammers have been chipping away and I've been feeling in in the second floor. But the frequency is very very low, right?. I've also seen a recording studio being built with a rubber isolated concrete pad but that construction seem tricky in a basement and probably very expensive.


Quote:
Originally Posted by hmmm5 /forum/post/15751684


wow. what a treat going down those stairs to this new area will be.

Thanks! I'm half done with some 3D models and have just begun to "feel" what it will be like.


One thing occurred to me which I need to figure out a solution: if I'm locked away in a basement soundproof box I need a way to monitor my young daughter at night 2 stories above me. Probably a motion detector wired to the theater, but I'm curious what novel solutions people have come up with.


Cheers,
 
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