Room Acoustics


Could somebody give me a few pointers on where to start, how to determine problems in a room and fix those problems? Perhaps a link to a basic starters page. Do acoustical panels really improve things alot? Can it be done cheaply?
lush
@kalali 

I agree with you. Note, however, the foam factory publishes a fair amount of specifications regarding their foams NRC absorption ratings. In fact they provide independent third party lab results too. So while what you are saying is true that they don't do much, they do *something* in the way of absorption. In my case I wasn't looking for much absorption, just something to take the "edge off" sound directly hitting dry wall.  http://halr.x10.mx/AV.jpg 

Also, according to what I was told by a GIK Acoustics rep, one needs 2.5 inches of foam for every 1 inch of their fiberboard. I went with 2 inches foam. 
Those "foams" are a bit too soft for doing much absorption or refraction. They do help a little bit with bass trapping if the speakers are very close to side and/or back walls. I'm using their 2" wedge foams in my study where I'm forced to keep my monitors in room corners.
Among the least expensive options is acoustic foam.

http://www.thefoamfactory.com/acousticfoam/acousticfoam.html

I'm told it's not as good as fiberglass and wool, but at a fraction of the cost it can be "good enough".
Definitely, acoustic panels improve the things very much. And you can have them very cheaply. Now-a-days different types of very effective but cheap panels are available in the market. They are attractive also. Please visit www.acousticmanufacturer.com/Noise-Barrier-on-Temporary-Fence-for-Construction-Site.html to know the details.
I tried Room Tunes and DIY traps but my EQ was more effective and looks much better! Canvas paintings work pretty well though and obviously integrate in the room so I use them also.
If you go to the audioperfectionist.com website and download the free journals, there is a very good describtion of how the author treated his living room. I have been to his house and you can't see the treatments. Looks like any living room. It also had the best acoustics of any listening room I have ever heard outside of a dedicated music room.
In brief, he took 2x2s and attached them horizontally along the middle of his walls, dividing the walls into two 4 foot high sections. Then 2x2s every 2 feet vertically. That divides the walls into 2foot x 4foot sections. Inbetween each section he placed 2x4 solid insulation from Corning, up to the first and second reflection point. From there back he left the spaces empty, although, I think you could continue the insulation and then cover it with something reflective like thick plastic sheeting or thin wood paneling if you didn't want the empty spaces. Then he stretched fabric, horizontally, over the whole wall , stapleing it to the 2x2s. Finally, he put molding all along the outside edges and one chair rail down the middle strip to hide the seams and staples. You would never know that the room had been treated, it simply looks like expensive cloth wallpaper. You could even use two types of cloth, one below the chair rail and one above.
The only commercial treatment he has is two ASCtube bass traps in the back corners.
It gets confushing if you don't have or want a dedicated sound room. How do you incoporate a decent sounding room with one you can live in? I'm in awe of some of the systems on here that have fully treated rooms. One comes to mind, I foget the members name but he uses Revel speakers and his basement is completely done up. What about the common man that uses his system in his family, living or even bedroom? I look at Bass traps and think to myself, not in my place. The acoustic panels look like they could fit in with some room decors though.
Interesting! I was just about to start Room Acoustic Thread myself and now I have lots to read. Thanks!
"Working on your room acoustics is probably one of the most important things you can do to improve the sound of your system."

I would go so far as to say that room acoustics is "THE" most important thing you can do to improve the sound of your system.
Working on your room acoustics is probably one of the most important things you can do to improve the sound of your system. It also allows you to better evaluate every change in components and is simply one of the best bangs for the buck around.

A good place to start is the Room Acoustics Forum (sponsored by Rives) over on Audio Asylum. In addition to the Rives site mentioned above, be certain to check out Ethan Winer's sites where he provides a lot of solid and practical informtion on the topic. Jon Rische's site also provides some good info.

There are a lot of DIY projects for bass traps and absorbers that can produce excellent results for not much money. Some are as quick and simple as Jon's "down and dirty" bass traps which is essentially stacking bags of rolled insulation in the corners of the room - they're quick and easy to do and gives you a hint of what is possible. I have built custom bass traps based on information from Ethan's site using Owenings Corning 700 series products of rigid fiberglass and other materials. Have also made absorbers for the first reflection points and a few other devices. The finished products are professional looking and have made a dramatic improvement in the sound.

The cost is relatively cheap if you have some basic skills and access to a shop. I made four 2'x8' bass traps (one for each room corner, four absorbers (walls and ceiling) for the first reflection points, and a couple of other bass traps for under $700. Depending on what your final covering material is, you can spend a little less or a little more.

You can also look at doing some rough measurements of the room acoustics using the Radio Shack analog SPL meter and the Rives Audio Test CD. Total cost for the two items is about $75. While still a course measurement, it gives you some of idea of what is happening in the room as you make changes.

Lot's more to discuss, but hopefully this will encourage you to try a few things.
Read this link it will tell you mostly everything you want to know, and is easy to understand. Also, it has a room calculator to tell you the proper dimensions for your room.It also has a link to a forum if you have any questions.

http://www.ethanwiner.com/acoustics.html
another approach that I did was to use the people at http://www.acousticsciences.com

All you ned to do is to provide them with photos of your room with measurement and where you are sitting and where your speakers and gear is.

They will then provide to you at no charge a CAD of their suggestions on the room modifications.

I used them and my room is flat at all frequencies other than a small 60 Hz bass hump which I can live with.

Acoustic panels do make a difference. Have a look at the photos of my room and you wil see the different size tube traps as well as the sound planks on the front wall.