That's true. I personally listen to Dennis and that's about it :)


I definitely agree with that. Too much exposed Dynamat can also weaken your midbass up. You don't want a room that's too dead or sound that's too unbalanced. The rest of the ideas were good.



I wish he'd post here more:
[Link: remotecentral.com]


Here's a couple of other good reads:
[Link: remotecentral.com]

[Link: remotecentral.com]

CJ

Do come back so we can blow your budget on all of our whimsical equipment suggestions..... then it will be just like AVS

LOL me first!

We had 3 whise subs in stock for YEARS that i might have been able to get you a deal on until the boss moved recently and put 2 of them in his home office. I had been trying to get them for my car :).

Well, since David never leaves the Batcave........
How did these end up in my pimp ride? :)

Wasn't the first one $12k ?

Mario,

Sorry to hear you were hit by the economy as well. A lot of us are in the boat together!

Several years ago, I was in a place similar to yours regarding my home theater. I bought a builder home that was spec. He had "prewired" for home theater. This amounted to 20awg 2 conductor inwall run to 5 locations in the room, and a single coax into the room. LOL

I decided to go the DIY route after trying to get several CI's here in Dallas to do something, and decided the ones I talked with were all more interested in selling me stuff, than getting the best sound.

I used this software:
http://www.etfacoustic.com/

You will need a microphone, and preferably an external mic amp/sound card.

I bought a Behringer ECM8000 for the mic, as it is reasonably priced, and is designed as a very linear measurement mic.

[Link: behringer.com]

The mic amp/sound card I used, is a M-Audio MobilePre USB.

[Link: m-audio.com]

I put the speakers in place (Or at least something representative to give you an idea of the rooms characteristics), and did a quick test of the room. (I would suggest having carpeting in place, as that will drastically change the characteristics of the room.) It will give you a good idea of what frequencies are cancelling, and which are being reinforced.

I then took some OwensCorning 1" thick Kraft Faced 707 and temporarily mounted it to the walls at the first reflection points. I also made some temporary "clouds" (2 layers of the 1" thick OC707, with the kraft peeled off the inner surface of one of the panels) and mounted them to the ceiling at the first reflection points with a 2" air gap. I just used some wood as a spacer, and some screw eyes in the ceiling, with some solid wire through the screw eye, and then through the panel with the wire bent to hold the panel in place. Just two held it, as it was meant as a temporary measure.

I measured, and then started moving panels, and adding panels. I and a friend would hold panels as the software made measurments, and decided what locations did what we needed.

In general, I covered about 60% of the wall area, and probably about 40% of the ceiling area. Over the ceiling the first reflection point, and over the seating locations gave me good results. The walls the first reflection point for the front speakers, the back wall, and some random other wall locations gave good results.

After knowing what I wanted/needed as far as panels, I made my own panels from the OC707. I used fabric purchased at a local fabric outlet here in Dallas. I used the old rule of something you can easily breathe through, that is a fiber that will not stretch with changes in humidity. You could of course also choose something like Guilford if you wish. I made the panels by beveling the edges on a table saw of the OC707, and then dipping them in a tray made from a gutter with end caps, filled with a 2 part epoxy meant for fiberglass work. Let them dry and then covered them.

I then used some Rotofast panel anchors to put the panels up.

http://rotofast.com/

Finally you can retest the room, and then choose a device in case you have any frequencies that remain that are still being reinforced. Something like the Behringer Feedback Destroyers work well. Since you know the frequencies of interest you can use the manual mode of the feedback destroyer to attenuate those, and then retest.

Finally, if your receiver has any room analysis / correction, you can run that. After doing so simply retest with the mic and software to make sure it hasn't made things worse.

I had a very good result. My system sounded much better. My wife thought that things sounded better in general, but specifically thought the bass had more impact, and speech is much clearer. When my wife comments on noticing the difference, that is a sign that it is quite dramatic, as most of the time she doesn't seem very discearning about audio.

Let us know how things go. Good Luck! This can be something you add to your tools for clients.

You need to be concerned, IMHO, with sound ingress. This either minimizes the dynamics of the movie or requires tons of power to overcome which leads to sound levels that to kids and females is excessively loud. You need HVAC duct work that moves a lot of air but at low pressure. You said the room was already built out but this may not take much as far as sheet rock repair goes to make this happen. 39 Cent Stamp mentioned the door if you do that you need to make sure you have an air return in the room. Check the do-ability out with your HVAC guy. One of the best scenes for this is the one in Apocalypse Now where the tiger jumps out of the forest.

When I designed the house addition, I spec'ed HVAC air return, so things like sealing the room from HVAC standpoint will not be an issue.
Still looking at things like doors, and while I found few companies that make doors specifically for home theaters, the roughly $2,000 is not something I'm willing to spend on the doors. I talked to my local door company and we're looking at doing a door with automatic door seal drop thingy. It's about $40 to put on the doors, but I haven't seen it yet.
To put things in perspective, I've been using the room ghetto style for a while, and currently we don't have any door at all, and it's not been much of an issue, other than occasional annoyance when some comes in from another room and the automated lights (in the adjacent room) turn on (10-15% for pathway settings).
I'm also not at all afraid to do any drywall repairs.

Usa a SOLID EXTERIOR door with the weather seals, much better than sealing an interior door. For even more isolation use a double door system. One that opens into the adjacent room and one that opens into your room. Both of these solutions are inexpensive compared to acoustical doors.

If you can lower the noise floor by doing sound isolation in the room it does help tremendously but that will eat some of your budget. If listening to your own heartbeat starts to get annoying then you have a good low noise floor in the room:-)

If not doing sound isolation definitely do some acoustic treatments. I suggest getting a good design unless you have the measuring equipment and knowledge to do it yourself. There are many aesthetic options, I am a big proponent that the room needs to sound and look good.

Using and exterior door at the door seal kit from Kinetics will workout well. The second layer of drywall with green glue is all you need for isolation. If the room is quite enough then move on toward acoustics.

Since the discussion is about soundproofing, I will spend a bit more of your cash. Build a proscenium (AKA stage, a big wooden box decoupled from the wall/floor filled with a lot of sand) and put the sub on that. Not only does it look cool and make it look much more professional ("wow there is even a stage") and can help with keeping distance (" no one is allowed on there" is easier to enforce with small kids than "don't touch the screen") but it will absorb the bass from the sub and make sure the vibrations are not transmitted outside of the room where they could become extremely annoying.

If you read other forums at all, every so often you hear of some guy with that "bad" neighbour that keeps complaining/calling the police every time the guy sits to watch a movie. Obviously most posters will characterize the neighbour as an a$$ but my advice and a few other people tends to be, politely ask the guy to go and hear what is happening. you would be amazed how many times the "little" bass in the guys HT gets transmitted through the ground and the neighbours home works as a resonance chamber so he gets large "BOOM, BOOM, BOOM" and his house feels like there is a massive earthquake.

PS the sand is important, it is not only for mass but also because it is many independent small particles. That is why the large punching bags are filled with sand (or at least something similar) if they where solid they would swing like a pendulum after the punch, but what happens is the first "row" of sand gets the full brunt but each grain rubs against the other and so there is friction as they move and sooner or later you have two grains going towards each other and there force kind on cancel out.

Mario I think all of these structural ideas will help you more long term if you look at from the perspective of how long will the electronics you buy be current. The box will be harder and more expensive to change than the electronics that will be out of date in a few years.

See if snap will cut a you a dealer showroom deal on their sound isolation products.

Guys, all great ideas, thanks. I have a lot of homework to do and design help from the pros definitely helps.
I wish my market would support more H.T. installations so that I could justify spending the time and $$$ learning this for myself, but as is, the $5-8K installs I'm involved in don't bring ROI to do more than what I'm currently doing.

I think you'd be surprised how relatively inexpensive this can be. We did a theater with the complete Kinetic Noise system and at retail it was 10-12K. That was for the floors, walls, ceiling, doors and HVAC.