Bass issues,,,,will new speaker help?


Hi again.
When I am in rear corners of my room the bass is heavy but is hollow at my seat, when I measured my room with REW, calibrated mic and meter I have a suck out at around 50hz to 63hz (over 10db down at lowest dip).
My speakers have a woofer high and low plus a slot loaded passive, top woofer is 68in tall and there is another about at bottom of speaker.......speakers are placed very close to Cardas rule in a 14X24 room with low ceiling (79in), my seat is 6ft from rear wall.
I have a feeling of what answer is but just in case I wonder if a different speaker with a single woofer low to floor would change anything or if it is a case of bass traps and compromise......thanks as always.
chadnliz
Chad,

Perhaps the "Cardas Rule" will not work in your room. I'd try repositioning the speakers closer to the wall and if that fails I'd put them on an adjacent wall and experiment there. Why lock yourself into a certain speaker location because of some rule that apparently isn't working for you???
yeah, you are sitting in the worst spot in the room. room treatments may help, also, you may want to try adding a subwoofer into the system and fine tune everything with its placement.
I have the same issue. My dip improved (narrowed the troubled band width and decreased the magnitude of depth a a little) when I added a subwoofer, though still bothersome. It improved again (decreased dip magnitude a little more) when I added passive high-pass filters to my mains and reintegrated my subwoofer, though still -6dB. I hope to improve it once more when I add a second subwoofer.
Chad,

In general, the Cardas Rule is a general starting point for speaker and listener placement. From there you must move your speakers and listening position for optimum results. When you stand in the corner, you are hearing bass that is all bunched up and lumped into a room mode. Apparently you have positioned your listening chair into one of the rooms null points and the bass is canceling in that spot. You must move your chair forward and backwards until the bass is natural, then adjust toe-in and width to suit. Of course, there is a strong possibility that your speakers are not compatible with your room and no matter what you do the bass will never be correct, but you must move the chair and adjust the speakers' positioning to give them their best shot. When you say your bass sounds hollow in your listening seat, that is a red flag that the seat is positioned in a null spot. Try moving things around and let us know what happens.
Checked out the system pics. Nice. Very capable.

That side wall is panelling, right? You can fur that out 3-4", only supporting and nailing it at the edges of each sheet and place 2" 703/705 behind it. Rock wool with a burlap/cotton sheet to retain it from touching is a more available alternative. If it's an inside wall, it's even easier and might not have to furred out as much. Drywall, done the same way, works too. The whole wall could be a membrane trap. Might have to get a bit creative around the floor registers. Then, there's that T-bar ceiling. Let me think about that.
Check out the Sumiko Master Set. There are two or three threads discussing it on A'gon. You've got great equipment and this is a very small cost to get incredible results.

Dave
Corner bass tri-traps or superchunks will help. if you can fill every corner with them top to bottom then I am fairly certain you would get a modest improvement -and not just in the bass suckout.
Thanks everyone for your help and compliments, One problem I have is the fact I have a dual use system with Projector so I am locked into the short wall plan.......I like it that way too.
I am going to play with seat position and adjust toe-in accordingly and also may finally hook up the Behringer and EQ the dips a bit (I know not to try too much as it may damage amps but I think I could do 6db and also take a 3db peak down at 80Hz)
On a goofy side note I placed a full size Air Mattress and placed it behind speakers and it helped a tad as a bass trap I assume, I found this benefit by accident at our last Audio Club party, I did try it in back corner but didnt really hear anything worth noting.
I am sorry to say I cant do much more than that for the time being because I am on fixed income and these energy and food cost's are starting to get scary for many people like me, every penny counts now so even DIY solutions have to go to back burner in the imediate future. I would change speakers by selling off ones I have but I better see what I can do with what Ive got for now. This is a rather stupid and obvios point but if I had tha bass in the right spot of my room I would be in heaven....DUH
You guys are great and thanks as always!
I know you said you have a projector, but I think if you try a seat at around 9' from the rear wall...the bass will improve a lot (the 38% rule).

Dave
I will have friends mov e seats up a foot or three and see if that helps, hell I will just stand there when I head down to the room and see if it looks like it would work. Thanks for the tips everyone!