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100 Posts
Discussion Starter #1
I guess it's finally time to start my build thread after a decade of lurking and learning from others here.

The “No Compromise” theater is obviously a bit tongue in cheek as EVERYTHING is a compromise and the budget it tight for what I have in mind.

The plan is to have a multi use space for sports and TV viewing that is also high performance with respect to movies and music listening.

I've considered a dedicated theater room and I do not believe the space will be used enough to justify the cost in this configuration.

I think I have reasonable expectations that this room won't be perfect sonically, but I'm ok with that trade-off for the amount of use it should get over the years as a multi purpose space.

I'm a DIY guy at heart but it would take me 2-3 years to do this project on my own so I plan to employ the pros to help expedite the process and move up the room completion date.

Interviewed one AV guy with experience building recording studios and a pro audio background. He went on and on about Live end dead end (LEDE) and how anything bigger than a 10 inch woofer will sound bloated and lack punch. He claimed to have built some famous TV host's (with pancreatic cancer ) theater in California but at the end of the day I don't think we would be a good “fit”. He essentially agreed after walking through the space with me and talking through the sound isolation techniques I had in mind (DD/GG/clips/channels/etc).

The next AV pro I am speaking with is HAA certified (the only one in my city). We'll see if they are up for taking on my project.

Nyal @ acoustic frontiers is another pro I'll be speaking with next week to get a feel for what can be done.

Below are pictures of what I have in mind and the current studding in the space.

Layout Challenges:

1. There is a main floor HVAC trunk line that needs to be moved about 3ft to be hidden by the eventual screen wall.

2. There is also a hot water safety tank that needs to be moved to make room for the main floor HVAC trunk line move mentioned above

3. There is an HVAC condensation line that runs into the slab and limits my room width to around 16’ at it's widest point.

4. One flex duct for main floor HVAC needs to be moved to allow for full 9’ceiling height in the main viewing area

5. The sump pit/sump pump will also be a challenge with the need to lower the noise it creates and to maintain access in the future. It will be concealed behind the screen wall but I may need to get creative with left speaker placement directly above where it currently sits.

6. Expense. Its a large space (800sqft) and the master bedroom sits directly above the game room making sound isolation a priority. I'll need to pull out every trick in the book to save on costs

Tentative gear list to follow

Interested in any thoughts, opinions or suggestions


100 Posts
Discussion Starter #3 (Edited)
Tentative Gear list

LCR: JBL 708i or JBL M2

Side Surrounds: JBL control HST or JBL CBT 50-la

Atmos:- considering skipping for now and just pre-wiring for 4 overheads

Subwoofer: multiple 18 inch sealed enclosures behind screen wall (?JTR RS2), possibly danley TH-SPUD under riser

Rack mount subwoofer amplifiers

Amplification: crown DCI 2/600N x3 powering LCR

Crown ct8150 powering surround channels.

Processor: monoprice monolith htp-1 with Dirac live bass control upgrade

Screen- 150" diagonal (130"wide) 16:9 AT - possible ambient light rejecting- may get silver ticket screen and DIY material using the silver ticket frame (severston microperf cinemagrey or TAT-4k or similar)

Projector- don't hang the projector until the room is done! considering Benq LK990 or other high lumen 4k models when the room is closer to completion

298 Posts
Looks like a cool project! I didn’t get a chance to completely digest and understand your drawings (nice work BTW), but here are a few thoughts for you:

Sound “proofing” is quite expensive. Suggest adding a door (slider?) between the theater and pool table room so you can cut back on full ceiling and some wall soundproofing in the pool room?

That’s going to be a long run to your A/V rack... is there anyway to get it closer? The cost on custom length cables really starts to add up when you have long runs (at least it did for me).

Make sure you run conduit from your A/V rack to the back of the screen wall and to your projector mounting location (likely will be swapping cables out over time). You seem pretty organized so I’m sure this is on your list already.

Re speakers behind your screen. I know it’s just a drawing, but I’d make sure you have room to move the subs side to side. Typically 1/4 off the room width is the ideal spacing off the wall YMMV.

I found ceiling speakers to be one of the the MOST impactful elements of my 7.4.2 theater. Highly recommend adding them in now vs later. You may wish to add 6; two over the back row; two between rows and two in front of the front row.

Regarding the back row, It feels to me like you are missing a set of wall speakers to really back that area work acoustically. I’d at least wire in some side walls. Personally, I’d be concerned that are would really adversely affect the over all sonic performance of the space given its narrower configuration. I’m sure you’ll get some really good advice from others on that.

One of my big lessons learned was adding mounting substrate (plywood) everywhere I anticipated needing to anchor things to the wall including speakers and acoustic treatments etc. Suggest adding panels of 5/8” plywood between the hat channel.

You should start thinking about where you are going to mount your projector now (didn’t see it on the drawing).

Regarding sound proofing... I added GG and 5/8” drywall in the joist bays, roxul safe and sound, clips/channel and two layers of 5/8” drywall w GG then acoustic GG all around between drywall joins and floor etc, putty pads I outlets, solid core door with a 5/8” piece of MDF secured w GG (weighed 200 lb). All my HVAC runs were flexible or lined with duct liner (linacoustic). In general it works well, but the bass still shakes the house. The dishes rattle in the kitchen and my wife is still messaging me “WTF” from time to time (I only have two SVS PB 2000). Not sure what you have to do to contain bass better. I’m disappointed about that. The door is absolutely the weakest link... fortunately, we added a pocket door on the other side of a small lobby and it cuts out a lot of sound (SPL deduction of about 8-10 dB) from the theater room.

Sent from my iPhone using Tapatalk

100 Posts
Discussion Starter #5
Thanks for the suggestions and input. The feedback is great.

Regarding the soundproofing, my current plan (subject to change) is to use clips and channels only on the ceiling and the wall separating the entry space/snack area and the main viewing room (load bearing in RED)+DD/GG over every gypsum surface in the room. (Good call on the 1st layer plywood)

For all the other walls without clips/channels, I plan to accomplish decoupling by erecting 2x4 walls spaced out 1” from the concrete foundation walls (or existing framing) then use ib-3 brackets to decouple from the ceiling joists above.

Regarding the floor, it's my understanding that serenity mat, Kinetics RIM system, etc. is the gold standard for floor isolation but costs can be an issue (I'm guessing close to $10k just for the flooring underlayment for this large of a space. At that price, I'm willing to look at less than gold standard alternatives that may still offer reasonable performance at stopping flanking paths. I've read of drycore as one option and building the framed walls on top of the drycore panelled subfloor. Also using dimpled plastic with OSB on top, then framing walls on top of that.

Anybody with a suggestion on how to decouple the concrete slab in a cost effective way? Horsestall mat cost?

I know a lot of the pros prefer clips and channels everywhere to avoid “wall impedence” issues, but I haven't ever seen any data to support that, and unless I can be convinced, that may just be another compromise I have to make to ensure that costs are controlled.

For the doors (there are 3 planned currently) I plan to use communicating doorways for all 3 openings with solid core slab doors and perimeter seals/automatic door bottoms. I think the $3k acoustic door will blow the budget as a manufactured solution.

I Also plan to use roxul s&s/thermafiber in all wall cavities and joists above but would pink fluffy work just as well to save on costs?

Regarding the AV rack location, there is actually a beam that runs between the foundation walls shown that I can run a conduit and 30 ft HDMI cable to the projector location (lens of projector just behind heads of 2nd row seating). The speaker cable runs are going to be long for sure and according to my calculations (wiring schedule below) will likely end up at ~$1k just for cables😲

Wiring schedule

Good point about room for moving subs. I may start out with 1 small sub when the room is complete to measure with REW to see how the bass response is at different positions and then get a plan together for how to best integrate the multiple subs required to fill the large space. I had considered making stands for the speakers (if I have the budget left at the end for the M2’s) that would allow space to put subs underneath (similar to another theater picture below)

For those interested in the 3d renders, its from a software program for architects called softplan. You can get a free trial version (with no end date) to play with by emailing from their website. The full program is crazy expensive and capable of much more and what you are seeing here is my neanderthal attempt at planning out the space.


100 Posts
Discussion Starter #6

I'm trying to think through different options for HVAC for the space.

Option 1.

Would be to have a “pizza box” ducted mini split unit mounted in the adjacent AV closet ceiling space, then running 8”supply and return flex ducts lines in the ceiling joist bays going to the main room and possibly the game room/entry space.

Option 2. (Likely much cheaper)

Would be to conceal a ductLESS minisplit into an alcove/mini closet up high towards the front of the main viewing room

Then have dead vents moving air to keep my family and I from hypercapnia. My thought was to bring fresh air into the space from the unfinished storage area via the game room, then exhaust the air into the AV rack space which should hopefully serve as fresh air for the AV rack space. (Plan to exhaust warm air from the AV rack to the outside)

My calculations based on 6 air exchanges per hour with 9 people at rest are below:

So unless my math is off I have to figure out a way to quietly move ~500+ CFM of air into and out of the theater via dead vents. That seems like a lot! Do I need 2 pairs of dead vents with inline fans?

Any thoughts on which option may be best or things I'm overlooking?


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