Bass Suckout in a Square Room - Remedies and Solut

Hi All,

My problem is I've got major mid-band and lower bass suckout with my speakers.
The bass dissapears in the seating position. But if you stand up either side of my sofa the the bass returns.
I would like to hear from anybody who has a similar problem and what solutions they use to eliminate the problem.
I can't move to another room in the house. But this is a dedicated hi-fi room. So there is a degree of flexibility.
Move things around. One of my audio rooms is nearly square. In fact, at 16x15x8, it approximates a half cube. You will have to move the speakers and listening position to find an useful arrangement. RPG makes an interesting program to help with this: There are more sophisticated but more complex programs to do similar things.

I doubt it's the room....try removing the couch! A friend had the same problem, after reading Jim Smith's book Get Better Sound, he saw the same situation listed and did as instructed by Jim, and no bass probs....try it and see what happens...
Also double check the polarity(+ and -) on your speakers and amps connections.
Do you happen to have your speakers on a long wall in a rectangular room? I'm 0 for 2 in good sound in that situation, the issue both times being the bottom is sucked out.
Your explanation is a little vague. Room dimensions and speaker/sofa location in the room would help, but you will have to move the speakers or the sofa.
If for any reason you can't move the sofa "WAF" then try using diffusors at the rear and side...the sofa is most likely the cause. I use for my listening seat a comfortable whicker chair. I figure if there is very little material at the listening position then any problem would lie somewhere else.
My room is 14 x 14 x 7 high, LOL. I finally tried a diagonal set up and am much happier. The bass improved immediately. It was deeper and well controlled in comparison to the conventional set up. Also much better imaging.

Good Luck !
Aggielaw, I have had just the opposite happen, with better performance with such a layout. I do sit quite close to the opposite wall which has quite a bit of absorbent room treatment.
The sofa is not the cause. If it is sitting in a null, moving it will not help but I have yet to find a sofa which is such a good bass absorber as to create a null.

Getting the listening position off the back wall and repositioning the speakers is important as is the use of true bass traps (at the intersections of room boundaries) to reduce both nodes and nulls.

Wrayman, You are absolutely right. A diagonal set up is a good idea and can produce excellent bass and over all sound include good depth.
The sofa itself is not the problem. The problem is where the sofa is located in relation to the speakers.
Meth, you suffer from standing wave, meaning you have low pressure and high pressure points at a frequency determined by your room size. Moving around till you find a sweet spot is really putting a band aid on cancer. If you listen carefully you’ll probably hear you have single frequency bass – no matter what your playing, the full bass sound will always be around the same frequency.

You need to add low freq some sound absorption to your room. A (fairly) cheap route is to buy a few sacks of R19 from home depot and stick them into a corner. You bass will tighten up and become more natural.

Experiment with speaker placement. The distance to the front wall and the side wall should not be equal. Experiment moving the sofa forward or back. GIK makes affordable acoustic panels and traps which are also decent looking. ASC tube traps are expensive but effective.
R-19 insulation is frequency selective. If you are going to treat your room use room treatment products. I have used Tube Trap products for about 20 years. I know they work.