Bass traps


What do they do? Specifically, will they help my anemic bass problem in the room? It's not the speakers.
homer
Speaker placement is the single most important part of the setup of a system and will in a big way determine the quality and quantity of the bass. Granted room demensions will also have a big effect on the bass responce of a room.
One other big words of advise is when placing speakers in a room do not have any accoustical treatment in the room. You want to place your speakers so one the bass is were you want it and the room has the least effect on the sound. You will hear it. Ive seen to many people, and many well respected audiophiles that try placing speakers with a room full of sound panels. WRONG As far as bass traps. Problem is that in order to effect bass in a room they must be very large. In wall Helmholtz resonators are the only way to effect the bass to any degree. They need to be built into the walls and holes drilled to tune them to the frequencys your trying to effect. Trust me try speaker placement first. lol Kevin
Thanks to Tobias and Pauly, I tried what you did with a couple of bags of Roxul Safe 'n Sound. It works! Better soundstage and tighter bass, more defined instrumental presentation.
So the traps will be on order soon since my wife is sure to discontinue uhmm.. services.. otherwise.
Bass traps can certainly help bring the bass out more strongly by lessening the megaphone effect that room corners have, thereby attenuating reflected bass frequencies that can phase cancel the direct bass from the speakers.

I use the Auralex Lenrd traps, three in each front corner in stacks and this made a noticeable imporvement to the bass response. It also cleared up the low mids.
Kal is of course right ("throwing in traps is not the way"), but I would just like to throw in that I tried something Jon Risch suggests along those lines. He mentions that you can buy a couple of bags of pink fibreglass and stick them in the corners behind the speakers if you want to know if a bass trap would change anything. I did that (you can imagine the WAF) and many things improved; not just bass, but also smoothness in the mids and imaging.

The pink bags are long gone, their contents in a wall somewhere, and an unfinished living room is still keeping me from installing anything better targeted to the space. However the memory of the improvement keeps me persuaded of the bass trap's viability. This particular measure was totally slapdash but boy, it worked well.
Bass traps can cure bass problems. They can help control standing waves which is dependent on the distance between parallel opposing walls and the floor to ceiling distance, and not on speaker placement. I used rolls of R19 stacked up to the ceiling in one corner of my room, and that tightened up my bass tremendously.

I also use R19 rolls to eliminate first order reflection off the side walls.

I am sure purpose built sound traps will work better.

Regards
Paul
Does the bass sound different in various locations in the room?

The second step would be to get a Radio Shack SPL meter and a test tone CD or software and determine if there is any suckout at the listening position and elsewhere. The severity of the recourse depends on the the results. If the bass drops directly in front of the speakers, there's probably an equipment issue. Bass traps are not created equal and are designed for a frequency range.
Instead of hit-and-miss, there are logical approaches to this which will maximimize the chance of success. Just throwing in panels and traps is not the way. Take a look at www.realtraps.com or www.rivesaudio.com for useful information. You do not have to buy their products to learn what sort of products you need for the problems you face.

BTW, I have experienced a significant improvement in the quantity and quality of the bass in one case where the listening position was in a null that was reduced by trapping at that frequency.

Kal
The room that I have is just too bright and I'm toning it down with Sonex panels. I'm thinking that by adding a couple of 4' corner bass traps it'll focus the bass more. It's not the speakers, wires, amps or the rest.
Speaker, speaker placement, cables, and your other equipment will determine the amount of bass produced.
Each is equally important.

Bass traps control bass boom and help define the tone and soundstage.
I am doubtful they can ever make a huge difference in the bass...an improvement certainly but I doubt you can turn anemic bass to strong bass response. They should smooth things out a little above 100 Hz in the frequency response ....but most of the benefit will be in reducing reverberation...i.e. cleaning things up...adding clarity when bass notes are close together.

I am waiting on my traps to arrive...so my comments is based on what I have read.