Need some help for living room acoustic treatment

Hi and welcome to AVSForum.

So, if I were you I would:

1. Buy a subwoofer and place it between the Left Front and the bookshelf by moving bookshelf a bit to the left.
2. Run Audyssey. Your 2809 has MultEQ XT on board. Set all speakers to "Small", set all crossovers to 80 Hz. You will hear a night and day difference, especially in the bass department.
3. Report back please.

Have fun.

P.S. If you are new to Audyssey please read the setup guide and follow it to the letter (in my sig).

A subwoofer is usually an integral part of a HT system, bass of a subwoofer is very hard to be replaced by speakers. While speakers are set up for imaging, dialog and surround effects, the low frequency range in a room has different acoustical propoerties than can only be handled by a subwoofer properly placed. Deep, smooth and even bass never coincides with speaker placement. You may read the blog "Small vs. Large" on the subject in my sig.

Again, if Ii were you I would try to find a way to place the speaker into the shelf, even if the lower shelf has to be taken out. You may look at my setup (in my sig) and see how I solved the sub placement.

Cross my fingers for your improved Sound Quality despite you "limitations". Compromise, compromis, compromise.

 

Acoustic treatments will always help, but you have to accept that they will 'impact' the living space aesthetically. The room is the single most important component in any system and taking steps to improve the room's acoustics is always worthwhile and invariably yields significant improvements in SQ - more so than changing any electronics and often more than changing speakers too.

 

The best place to start learning about acoustic treatments is on either the Realtraps or the GIK Acoustics websites. Both have tons of educational material there.

And "deep smooth and even bass" never coincides with a single predetermined subwoofer placement. Although I agree typical home speakers can usually never reproduce the SPL and low frequencies that a real subwoofer can, having bass from 5 locations will be much better than bass in only one location.

Gistum, do you know the tuning frequency of your speakers? You may want to pull the port bungs out. Set the receiver to subwoofer at 40hz so that the speakers are filtered below their tuning (damage can happen when a speaker tries to play below tuning). Re-run audyssey. See if that's better. If it's not, try one more thing. Stick a little wad of stuffing in the ports. Like insulation or pillow stuffing. The port bungs essentially make the speaker sealed. This will make them sorta in between. Aperiodic. It'll reduce the port output, but still have more than sealed.

That's free to try, so try that.

I have had my fair share of setting up nice theater setups in less than ideal rooms as well as helping friends and family improve their not-so-great setups to make them sound good.
Here are my suggestions based on my experience. I feel each of them will help improve your sound and theater experience without bothering you much aesthetically.

1. If you don't already have thick curtains for the large sliding glass door, get some. Either cloth curtains or some of those solar blocking ones. Then close the curtains when you watch movies.

2. Buy an Auralex Gramma for $50, cut it in half, and put each half under one of your tower speakers. This will isolate them from the tile floor.

3. Buy a runner carpet for the long area that goes beyond the living room. That will help knock out some of the echoing and boominess.

4. If you can, angle the rear speakers so that they will be pointed toward the center seating position of the couch. You will get a better surround sound effect this way. You can either use some L-brackets to mount the speakers at that angle or you can just built some small shelves for the speakers to sit on.

5. If this won't bother you, put an artistically designed blanket on the back wall above the couch. This will provide some acoustic treatment without costing much and although it will not be as effective as acoustic foam, it will look a lot nicer because it will look like it is there as a decoration more than for acoustic purposes.

If the depth of the bass (frequency-wise) that your tower speakers are putting out is good enough for you and you don't think you want even lower, more rumbling bass, then you don't need a subwoofer. Getting a subwoofer is not going to help with your boominess problem. Your problem seems to caused by your room from what I can see.

Try these free/cheap things and see how your setup sounds. Report back and we might have even more ideas for you.

Ok, I'll try to be more clear.

Trick your receiver into thinking there is a subwoofer below 40hz. That way you won't overload your speaker. This is somewhat optional. You don't have to do this. It just may protect your speakers.

I thought you were running them sealed. In this case, try stuffing the ports with some pink insulation or pillow stuffing or something. It'll restrict the vent and lower/suppress the tuning and output. This is free to try and may help the boomyness.

The solution is very simple: You need bass traps. I bet you knew that already.

--Ethan

But if he has no where to put them...

I trust Ethan will come out with a solution. Let's wait and see. Ethan?

 

Ah right, OK, I misunderstood you. In the absence of room treatments, all you can really do is take care of speaker and sub placement as best you can and, if you have an AVR that has Audyssey MultEQ (preferably XT32) then run Audyssey, which will do a good job of EQing your speakers/room. WRT to the quality of the bass, this is heavily influenced by the position of the sub in the room. Without any form of measuring gear it is difficult (but not impossible) to find the best place to put the sub. I would suggest that you get a cheap Radioshack SPL meter. If you do, or can borrow one it will help a lot. If you don't have access to the meter, put the sub on your listening chair (raised to ear height if poss - use books to stand it on) and play some deep, consistent bass through it. Then crawl around on the floor listening to the quality and quantity of bass. There will be one place (or maybe more than one) where the bass suddenly 'pops' into 'focus' and sounds good. That is where you should put the subwoofer. The laws of Unintended Consequences usually put that spot in front of a doorway etc, so if this is the case, keep trying until you find an acceptable spot - there will usually be a choice. 

 

This is an alternative to a 'sub crawl' where you move the sub around the room and listen from your normal listening position. That method is just as good but my method gives the same results without you having to drag the sub around the room which can be tiring if the sub is very heavy. This is a useful site to learn more: Audioholics Guide To Subwoofer Placement

 

If you can't find a suitable, practical spot to put the sub where it sounds good, then you may have to consider moving the listening position.

 

I forgot to mention the AntiMode as an alternative to Audyssey. This is a  relatively inexpensive bass EQ component that has had very good reports. Google it to learn more.

 

All very good points. WRT to the one I bolded, he could use some proper bass traps on the wall and hang the blanket over it as well. Or get some of those traps that come with artwork already printed on them.

 

This is one of the problems of not having a sub - you have no flexibility in where the bass comes from because the L&R speakers have to be where they are for imaging purposes. It's also probably an issue that your listening position is hard up against the back wall.  Can you not put a sub where I have indicated with the red square? Probably less than ideal, but maybe better than no sub at all.

 

 

 

Do you need a three seater couch? If you could manage with a two seater, you could fit a sub to the side of the couch and use it as a lamp table or side table.

 

I can see the difficulties your room presents. Do you have an AVR with Audyssey?

With acoustic treatment you can have:

• Effective
• Attractive
• Affordable

Pick any two.

Seriously, first you have to decide if appearance matters more than sound quality. You can have good acoustics without seeing any panels, but that requires false walls which is expensive and takes yet more space from the room. I can help you with the technology, but not appearance or cost. This short article explains the basics in plain English:

Acoustic Basics

--Ethan

Worst? Probably the strong reflections coming from the wall directly behind your head.

--Ethan

The ideal back wall absorber would absorb equally well over a wide range of frequencies.

The conceptually simplest would be to build what is in effect a false wall approximately 4"-6" away from the existing wall, covered with fabric, and with a 2"-3" thickness of acoustic absorbing material (high density fiberglass, rockwool, or cotton waste) spaced 2"-3" away from the existing wall. Since the wall is not structural the vertical members could be thin lumber such as 1 x 4 or 1 x 6 (the missing 1/2" wouldn't make that much difference), and be spaced 2' to 4' apart so that the absorbing material (which often comes in 2' x 4' batts) fits in-between. Try to work things out so that the seams in the fabric are handled tastefully. I've installed absorbers like this and they are effective down to 50 Hz or so because their area is so large.

Yes. That corner adds an acoustical asymmetry to the room. The trap should be floor to ceiling and fill the corner at least a foot or two along the walls There are several ways to add absorbing material:

(1) Simply fill the space with less dense absorbing material
(2) Use higher density material just behind the cloth covering that is stretched across the corner, and leave an air space behind it Air spaces can be as effective as absorbing materials when used with them.
(3) Bisect the corner with the absorbing panel.

Room sonic treatment's figure of merit is the surface area of the entire room divided by the area covered by acoustical material. There is a right amount and it is possible to go overboard. The usual mistake is to use too little,

There are places where acoustical material is more effective or less effective. Corners tend to be areas where you get more effect from a given amount of material and this includes the place where the ceiling meets the wall. Reflections off of side walls need to be managed.

You are limited in terms of what you can do to the floor because it has an important and well-defined important function (supporting people walking about), but this is not necessarily true of the ceiling. I can't imagine a 4 or 6 inch thick absorber covering all or part of a floor, but I have seen them on the ceiling, particularly a few feet in front of the speakers.

A good sounding room has a mixture of reflection, diffusion, and absorption. Usually diffusion costs the most per square foot covered, but its favorable influence is not to be dismissed. Diffusion and absorption are interchangeable to some degree.

The site linked below is chock full of examples of many different kinds of acoustic treatments. I'm not saying necessarily buy stuff from them (but why not?) but at least look at their wide palette of options to expand your mind:

http://www.rpginc.com/index.cfm

Arny answered you in great detail. Let us know if anything is still unclear.

--Ethan

Check out these sites and see if there is anything you like. The decorative products that they offer would be the best solution for you for the wall behind your couch.

http://www.acoustimac.com/acoustic-panels/acoustimac-decorative-collection/

http://www.acousticalsolutions.com/792~acoustiart-sound-absorbing-panels

You have received many great suggestions here, some you have shot down for decorative reasons, so my suggestion may fall in that same catagory too. A subwoofer is the first good suggestion, measuring is the second and it isn't very expensive. We will get to measuring if we don't lose you first.

Depending on how handy you are you may be able to build your own bass traps. Here are photos of my bass trap build.








I takes some work but makes a difference. Let me know if this interests you and I will show more photos of how to build panels for the wall behind the seating location.

I am looking to build some DIY absorbion panels, and was wondering what you guys think of using either OC 703 or OC 705? What are the differences between them? I have read that it is best to go with 4 inches of insulation with a 4 inch air gap between the insulation and the wall. Is this correct? I have not been able to find any OC 703 or OC705 locally, so I am now considering the pink fluffy stuff from Lowes or Home Depot. If I do end up going with the pink fluffy stuff, what is the best kind to get, and should I stick with 4 inches thick with a 4 inch air gap? Any help or advise would be greatly appreciated!

I don't know the differences between 703 & 705, I was able to find 703 locally, I buy it from an industrial supply company. Where are you located?

ATS will ship to you: http://www.atsacoustics.com/cat--Fiberglass-and-Mineral-Wool-Batts-and-Boards--106.html

They sell all the material and hardware to build panels.

I answered your PM before I saw this post. My Density Report shows the difference between the various fiberglass types.

Fluffy fiberglass works too, but only when it's very thick, like 12 inches. For 6 inches thick or less you should use 703 or 705. Your profile doesn't show your location, but this place has branches around the US:

SPI Company

--Ethan

The last digit of the model number (3 or 5 in your example) is the density of the fiberglass insulation in pounds per cubic foot.

Sound absorber design done involves selecting the right absorptive material for the application. There is a spread sheet you can download from

http://www.whealy.com/acoustics/Porous.html that sheds quite a bit of light on this issue.

You might want to search AVS to find any of the many threads about designing sound absorbers.

^^^^
Thanks for the link.

I post the research on it in this brief post: http://www.avsforum.com/t/1407637/the-room-acoustics-master-disagreement-thread#post_21955374. As you see there, lower density is better..