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Discussion Starter #1
Full disclosure, I started asking some questions in the “General Home Theater and Media/Game Rooms” forum, but I think my build will make more sense here. It’ll be movies and TV. No bar, no gaming. Just some quality sound, a big, bright picture, and enough comfy furniture for me and my wife.

We’re in the design phase of building a new house, and I talked my wife into a main floor media/theater room. I won’t go into all the details in one post, because no one will read it all, so I thought I’d start with the basic layout. It’ll be relatively small as these things go: 15’ x 11’-11” x 10’ high. I can’t really move the door or the closet, but the windows can be played with a bit.

Since we first came up with the house design, I was thinking of putting the screen on the short (West) wall opposite the door. However, it dawned on me yesterday to see what it looked like with the screen on the long (South) wall. The attached pics show what I’m thinking. The thicker colored lines denote Anthony Grimani’s recommendations for speaker locations, and the thinner lines are Dolby specs. The pics also show the calculated room modes and the seating depth based on those.

As for picture, the West-facing layout is shown with a 107” wide screen, giving a viewing angle of 48.8 degrees. The South-facing layout uses a 96” wide screen with a viewing angle of 54.1 degrees. I plan on a JVC projector (NX-7 or similar), which should be able to handle being offset from center. I also plan on using a retractable screen so I can have a TV behind it. According to my wife (and I kind of agree), sitcoms and the like should not be watched on a big screen.

I’m already thinking about all the other details, but I figured I’d start small on the thread. Any input is appreciated.
 

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What about moving the seating distance a little closer to get the speaker placement in-line with recommended angles and actually having a place to mount the speaker? would that be too close to the screens? I like the diagram with the display on the west wall.
 

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I would put the screen on the south wall. More lateral room to play with plus having the door open in that area will make it feel much nicer to move around. Plus having a bigger screen is NICE.

I don't know what that lollipop thing is in the digram for the South wall setup, so I cannot comment on that.

Finally, I agree: If you are going to watch TV with a couple lights on, having a direct view TV available is super smart.

(The only reason I would choose the west wall for the screen is for non projection reasons: If you are, for example, a big time two channel music person, and want to be able to look out the windows at a nice view while listening to music during the daytime, of something like that.)

By the way, don't skimp on serious blackout curtains in a room like this. Windows are nice but you need it to be as dark as a room without windows when using a quality projector like that......otherwise it is like listening to a high end stereo while someone is running a blender in the seat next to you....

And while small rooms can sound PERFECT, they require serious room treatment to sound their best, and sometimes windows can be in the wrong place vis-a-vis room treatment. So if you have flexibility with window placement, consider where treatment will need to be (eg, first reflection points, rear wall, etc) before locking in the window locations.
 

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So I have seen a few of these sound peak and nulls charts and I was wondering is this an auto calculated thing like from a website and if so could you provide a link please? thank you.
 

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I have seen a few of these sound peak and nulls charts and I was wondering is this an auto calculated thing like from a website and if so could you provide a link please?
It's the Harman room mode calculator. Free download at the bottom of the following page: https://www.harman.com/audio-innovations (lots of white papers on that page worth reading).
 

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The thicker colored lines denote Anthony Grimani’s recommendations for speaker locations, and the thinner lines are Dolby specs. The pics also show the calculated room modes and the seating depth based on those.
Whichever wall you end up facing, you and your wife will experience different combinations of peaks & nulls at different frequencies due to the width modes of the room. You can cancel the first 3 of those width modes (and ALL their peaks & nulls) by simply placing a pair of subs at the ¼ and ¾ points of room width (front wall or back wall or even behind the couch). This will give you smoother bass AND greater consistency from seat to seat. Explanation below from Floyd Toole:

 

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Discussion Starter #7
What about moving the seating distance a little closer to get the speaker placement in-line with recommended angles and actually having a place to mount the speaker? would that be too close to the screens? I like the diagram with the display on the west wall.
Assuming you're talking about the west-facing option, I wouldn't mind possibly going a little closer to the screen. Probably the next logical place moving forward would be about 9' from the front wall. That would get the right side speaker past the closet and get past the 151Hz null.
 

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Discussion Starter #8
I would put the screen on the south wall. More lateral room to play with plus having the door open in that area will make it feel much nicer to move around. Plus having a bigger screen is NICE.

I don't know what that lollipop thing is in the digram for the South wall setup, so I cannot comment on that.

Finally, I agree: If you are going to watch TV with a couple lights on, having a direct view TV available is super smart.

(The only reason I would choose the west wall for the screen is for non projection reasons: If you are, for example, a big time two channel music person, and want to be able to look out the windows at a nice view while listening to music during the daytime, of something like that.)

By the way, don't skimp on serious blackout curtains in a room like this. Windows are nice but you need it to be as dark as a room without windows when using a quality projector like that......otherwise it is like listening to a high end stereo while someone is running a blender in the seat next to you....

And while small rooms can sound PERFECT, they require serious room treatment to sound their best, and sometimes windows can be in the wrong place vis-a-vis room treatment. So if you have flexibility with window placement, consider where treatment will need to be (eg, first reflection points, rear wall, etc) before locking in the window locations.
Nathan, you make some good points. I do like the idea of more lateral room. As for the screen size, it'll actually be smaller (won't be able to fill the next size step up from that throw range), but it will appear larger. Can't complain there.

We actually planned a large picture window in the middle of the West wall for quite some time. We should have very nice views in that direction. We were going to have the TV on an in-floor lift, but then I figured I didn't want to hassle with it. I could go back to the picture window idea if we use the South wall layout, but I think the smaller windows would work better for sound treatment options. Any idea where I can read up on room treatment placement? I don't think I can do much with the North wall window. That's the front of the house, and my wife probably won't allow too much fiddling there.
 

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Discussion Starter #9
Whichever wall you end up facing, you and your wife will experience different combinations of peaks & nulls at different frequencies due to the width modes of the room. You can cancel the first 3 of those width modes (and ALL their peaks & nulls) by simply placing a pair of subs at the ¼ and ¾ points of room width (front wall or back wall or even behind the couch). This will give you smoother bass AND greater consistency from seat to seat. Explanation below from Floyd Toole:
Sdurani, thanks for chiming in. It was your explanation of the modes in the previous post I made that got me looking into that stuff. I read about having to deal with the width modes, as well, but I had no idea about the subs being able to cancel some of that out. I will definitely have multiple subs, though it does look like sub placement could be a problem in this room. 18" end tables? I updated the layout pic with the width mode diagram. That should help me keep this stuff in mind.

One question on that. If I have my subs crossover at 80Hz, wouldn't they be of little value in dealing with the modes above that?

And FYI, my wife also likes the South-facing option.
 

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If I have my subs crossover at 80Hz, wouldn't they be of little value in dealing with the modes above that?
You can extend the mode cancelling up to the first 5 width modes by centering the woofers of your L/R speakers at the 1/6 and 5/6 points of room width. The reason I said woofers is because we're talking about cancelling modes in the bass range, which have the largest peaks & nulls.

Graphically, it would look like this:





Subs are in the 2 nulls of the 2nd width mode (black trace) and L/C/R speakers are in the 3 nulls of the 3rd width mode (red trace).
 

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Discussion Starter #11
You can extend the mode cancelling up to the first 5 width modes by centering the woofers of your L/R speakers at the 1/6 and 5/6 points of room width. The reason I said woofers is because we're talking about cancelling modes in the bass range, which have the largest peaks & nulls.
Okay, now we're talking speaker placement. In the 6 or so hours of AV ProEdge/Anthony Grimani videos I watched, he noted several times to put the front L/R speakers at 22.5 degrees (45 degree total arc from the listener). Apparently going wider just doesn't sound "right." That would mean placing my front L/R speakers under the screen since I don't want to use an acoustically transparent screen at this viewing distance. That would actually be at right about the 1/4 and 3/4 positions.

Putting them at the 1/6 and 5/6 locations would end up being something more like 35 degrees. That seems like quite a difference; it's even outside of Dolby's recommendations. I planned on DIYing speakers, most likely from DIYSoundGroup. Would their designs (most of which use a compression driver on a waveguide) be able to realistically "make up" for this extra width?
 

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Putting them at the 1/6 and 5/6 locations would end up being something more like 35 degrees. That seems like quite a difference; it's even outside of Dolby's recommendations.
You asked about mode cancelling above the crossover point, so I told you the speaker locations that would accomplish it. You don't have to use those speaker locations IF mode cancelling is not a priority above crossover. BTW, there's nothing wrong with prioritizing placement for a wider soundstage over placement for mode cancelling. You're armed with the info, so you know which compromise to choose.
 

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Discussion Starter #13
You asked about mode cancelling above the crossover point, so I told you the speaker locations that would accomplish it. You don't have to use those speaker locations IF mode cancelling is not a priority above crossover. BTW, there's nothing wrong with prioritizing placement for a wider soundstage over placement for mode cancelling. You're armed with the info, so you know which compromise to choose.
Yeah, I get that there will be a lot of tradeoffs in this project. Like everyone else, I'm just trying to figure out the best way to bring it all together.

I'm trying to be more particular about the soundscape in this room than my current basement theater. That being said, I've got a lot of research ahead of me.

Luckily, I've got a lot of time; the house plan is just going out for bid today.
 

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Discussion Starter #14
Has anyone put a projector in a closet? I've been reading a little bit about hush boxes, but it really wouldn't be that similar. With the current closet measurements (I may make it la little wider), I think it's something like 135 cubic feet. Would I need to worry about additional cooling/venting?
 

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something from here. this is my go to source. https://www.acinfinity.com/
Great. Looks easy enough. I've got a few follow-up questions.

My wife likes the bifold door idea so they don't protrude very far when open. However, the closet-specific options require a 15.51" hole. So the door won't work, and with 16" OC framing, I don't expect the wall would work either. What about making a smaller enclosure within the closet for just the projector, and using some of the narrower fan options? I plan to put the rest of the equipment in an unfinished area of the basement below the theater anyway.

Not knowing much about this stuff, I'd kind of prefer just to go with normal doors and mount the stuff in them. I figure solid doors would make for a quieter projector, and I'm not sure if you can get those in bifold. If I can talk her into this route, would it matter that the projector would be offset from the actual location of the intake/exhaust?

Okay, I just had another idea before hitting "Submit Reply." If I used the whole closet space with no internal project enclosure, I could use several of the "normal" intakes/exhausts spread across the width of the closet. These would easily fit within the framing.

Any preference? Does it matter beyond aesthetics?

Last question, when calculating "Optimal Cabinet Fan CFM Recommendations," I came up with a requirement of 450CFM. Do you add the sub-total of intake and exhaust fan CFMs together to get your total? I assume yes, but I want to make sure.

Thanks.
 

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As you are asking for advice and I have the exact same size room projecting to the longer wall and although we have a 3 seat couch with end seats that recline the center seat gives a little breathing room and a great place for the large tray to sit holding the pizza or snacks or once in a while a friend.

I have had FP media/HT for close to 20 years the first being a multi row conventional HT in the basement and in this new house we wanted a media room for two and right off the living room where it will actually feel normal to use every day.

I kept it simple 5.2 sound with large full range fronts and two 12” subs below them. Screen area for IMAX immersion for those movies and scope movies and zoom down for TV viewing. The living room is bright and light colored and the media room is dark colored with black ceilings and no windows by design and is entered thru an arch way that has black BOC curtains for the rare daytime movie viewing. The projector goes on around 7:00 each night and runs till midnight or later. Being retired is great.

The screen is dark gray and the room has 2 modes of lighting one being zero lights for movies the second is carefully controlled task lighting for TV and casual viewing. Keeping the viewers end of the room brighter than most think possible for front projection and the screen end still dark. We have zero desire for a much smaller flat panel TV and our eyes to screen distance is 8’.

It is easy to get wrapped up in the audio angles and all that. I know it is not correct but to me it sounds amazing and very much good enough for all our needs. :)
 

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I would use the west wall for the screen and ditch those 12 inch wide windows...if they have to be there for exterior looks, then just disregard them and cover them up inside, screen wall style.



This will let you be able to move the seating forwards and backwards and possibly give you more latitude in finding the best sound/viewing distance you like.


It will also open up more PJ choices due to throw distance.......



I am no pro, just a enthusiast......but these are issues I encountered in my 12x12 room..........



Screen size changed several times and ended at 120 and the seating against the back wall......which creates a lot of sound problems, PJ choices were very limited .



I also found a AT screen with the center behind it in the proper place to be very desirable out of all the configurations I had. Also using the screen wall made a huge difference allowing many configurations and adjustments to be made allowing unlimited speaker choices and sizes.


You might get it perfect the first go, but using in walls and a non AT screen make changes much more difficult and limited.......The screen wall allows changes to be made easily in both speakers ,placement and screen size.



Just my 2 bits, might help, might be useless........
 
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