AVS Forum banner

Status
Not open for further replies.
1 - 20 of 23 Posts

·
Registered
Joined
·
150 Posts
Discussion Starter · #1 ·
Greetings all,


In my plans for redesign, I'm stuck on where to start. One fundamental question is whether or not to undertake the construction effort required to seal the room. From a sound isolation perspective, this is more of a "nice" than a "must." However, from an acoustics-perspective, how important is having a sealed environment with which to work?


Two factors that jump out to me are that if I seal the room, I get dimensions of 16 by 17.3 by 8, which seems like it would create a difficult set of acoustic challenges. Also, without drastic redesign, the doorway would have to be fairly narrow, making it very difficult or impossible to get things like sofas in and out of the room. I could always bring in a side wall to fix these two issues, but that brings me to the major construction level again, raising the "how important is sealing the room?" question.


If the answer is "seal the room," I can provide a sketch if anyone wants to take a stab at design ideas.


Thanks for your thoughts.
 

·
Registered
Joined
·
3,991 Posts
Sealing the room becomes important for two reasons: Keeping the HT sounds from disturbing the rest of the house, and keeping the rest of the house from disturbing your HT sounds. As far as room accoustics are concerned, I don't know that it is that important, other than sound getting behind your walls and propogating down to another region of your HT. Someone with more knowledge will hopefully chime in.
 

·
Registered
Joined
·
7,655 Posts
Please explain why you feel that sealing the room will force certain dimensions of the room and the door.


There are many ways to accomplish this. Let us know your thinking so we can help.
 

·
Registered
Joined
·
150 Posts
Discussion Starter · #4 ·
Ah, sorry for being vague. Right now the room is open to the rest of the house. There is a half wall ~40" height across most of the back of the room that borders a stairway (my room is on the 2nd floor). Further, the entrance to the room doesn't have a door and is open to the hallway.


I'll upload a diagram of the room and post a link to it later today to help me explain the layout.


Thanks.
 

·
Registered
Joined
·
457 Posts
bart,

As you can see from these pictures, I have a very large arched opening to the side of my Theatre. Obviously, I have all kinds of sound the gets out into the "lounge" area, but I'm actually surprised that it's not louder than it is. Maybe I'll get a sound meter sometime and try it!


This was simply one of those design considerations where the layout took precedence over possible sound issues. Now, there are probably all kinds of acoustic no-no's with this design, but honestly, it really works well for us.


Although construction details that "seal" a room like mine might seem fruitless, there is still alot that can be done. I used to think people who obsessed about caulking around electrical boxes and recessed lights were nuts. Not anymore. Just a few sweeps with the AVIA test patterns, and you will find that anything that touches anything else, but is not glued, screwed, or sealed, will resonate at some frequency.
 

·
Registered
Joined
·
262 Posts
There is one major advantage to a sealed room, and that is it is easier to get reference levels, especially in the bass area. And open room will let more sound "out" therefore requireing you to fill more air space with sound.
 

·
Registered
Joined
·
272 Posts
Any suggestions for doors? I have an opening I am going to have framed in and wonder what I should be looking for in doors? Something affordable I can get at Home Deport or Lowe's...thanks
 

·
Premium Member
Joined
·
4,827 Posts
From a soundproofing perspective, the best bang for the buck for doors is to go with a pre-hung, exterior grade (i.e., weatherstripped) solid core door...that will seal in/out a great deal of the noise. Available at Lowes, Home Depot, etc.
 

·
Premium Member
Joined
·
8,712 Posts
Quote:
I'm guessing pocket doors are a lost cause?
Nah. Not at all. Their rattles will keep time to the music and, who knows, their banging around might add realism to your bass. :)
 

·
Registered
Joined
·
7,655 Posts
I looked at your drawing. You can still change the dimensions of the room by building false walls. On the left side of your diagram, there is a little 'notch'. You could easily build a wall 6-8 inches inside the left wall and bring it straight back to the rear wall. Put the door in the current open doorway.


On the rear wall, just fill in the half wall all the way up. This will break things up a little.


I am not sure which way you were thinking would be 16'. I am assuming the width. If you do as I suggested, you would have 192 - 6 - 4.5 or 181.5 wide (15' 1.5"). While still not ideal, you are changing the relationship of width to height by about 6%. That is not insignificant.


With the addition of some well placed abosbtion and a little diffusion on the ceiling, you can probably minimize at least the majority of the doubling nodes.


A couple of other observations.


I know a lot of people do it but you will never get good sound or surround from that couch against the rear wall. Doesn't look like there is much you can do about it though. Just don't expect a lot from that position.


Your speakers, as located, are actually a bit close together for the listening distance. Besides, where they are according to the drawing, they are actually inside the screen frame. Try moving them each another foot out. You will get a better image and not block the screen.
 

·
Registered
Joined
·
150 Posts
Discussion Starter · #13 ·
bpape,


You are right with regard to the 16' (192") being the width and I like your idea of moving the left wall in, especially to eliminate the notch that just can't be ideal for that left surround. The only thing about only doing the left side is that it shifts the center of the room. I'm not sure how much my projector will shift its alignment w/o being physically moved. I guess if I'm building new walls though, moving the projector is small in comparison.


If I put the door in the open hallway, I'm afraid I won't be able to move anything in or out of the room. I should have put a dimension on the drawing, but it's only 34 " wide. Isn't that a bit too tight for a 30" wide door?


With the speaker location, you're right: it does look like they would block the view in my drawing! In real life, fortunately, they are just to the outside of the frame on either side. I may try moving them out a bit as you suggested anyway.


Thanks for all the helpful feedback.
 

·
Registered
Joined
·
7,655 Posts
Here are 2 options.


Option 1. Not knowing what room is to the left of the theater, this may not work. If you can, go ahead and move the left wall in but cut the corner of the open doorway. Yes, this will intrude into the next room. That way you can put the door in at an angle.


Option 2. Same concept, less work. Possible acoustic implications. Don't put the door parallel to the left wall. Come from the corner of the opening and angle it back toward the 2nd row riser. Would not have to be splayed much to allow even a 32" door. Maybe only 20 degrees or so would do it I think.


As for the centering thing... You really don't WANT to sit in the center of the room. If you do, you are going to hit EVERY even width harmonic node dead square at your ears. You do, however, want to sit centered to your speakers and screen. By moving this wall, you are really only 6" off center anyway.


Just a thought.
 

·
Registered
Joined
·
7,655 Posts
I made some quick mods to your drawing to show what I am talking about in option 2. I can't put it up because it is too big. PM me with your email and I will send you the modded drawing.
 

·
Registered
Joined
·
617 Posts
I dug my basement 21" to make enough room to totally isolate the HT from the rest of the house...the concrete floor is the only solid contact point.

Ceiling joist are between the floor joists above, and the walls are built inside the old room so no contact. It took a while and a bit of $$$, but was worth it. Example...

I was using one of those nail guns that use the 22 charge the other day, and my wife couldn't hear me firing that thing off. I fired 4 nails into the concrete which made me wince despite being all dressed up in goggles and ear protection. I was in the basement, and she was on the 2nd floor...normally we hear most noise (let alone gun shots) from that distance. The HT doesn't even have a real door on it yet... So is isolating the room necessary? I don't know...is it cool? yup!

:)
 

·
Registered
Joined
·
3,991 Posts
Quote:
Originally posted by scott jensen


I was using one of those nail guns that use the 22 charge the other day, and my wife couldn't hear me firing that thing off....


....is it cool? yup!

:)
I'll say this for DIY HTing....It's exposed me to alot of cool stuff and given me a good excuse to buy cool tools...First time in my life I've used a 22cal nail gun and a pneumatic nail gun. Fun stuff :D
 

·
Registered
Joined
·
306 Posts
As said before sealing a room helps limit unwanted sound from the HT disturbing the rest of the family or neighbors, but also limits unwanted sounds from disturbing people in the HT.


Imagine if you were watching a movie while you wife vacumed, one child was on the telephone, and another child was playing loud music in another room.


However sealing a room is not enough to get good sound while in the room. You also want a symmetrical room layout with control over how sound is reflected within the room. That has a big impact on the quality of the sound at different locations within the room. The sound reflections within the room can make the difference between an acoustically perfect listening room and one which sounds terrible.
 
1 - 20 of 23 Posts
Status
Not open for further replies.
Top