Hey Dizzydev,
Sounds like you need some good room correction to fix your standing wave (and probably bass cancellation) problem.
Most likely a job for your pre-processor or receiver. I went with the Emotiva XMC-1 to have the DIRAC room correction to fix the sound in my home theater too.
I hope you get it solved, happy listening,
God Bless,
Wayne

Dizzydev,

I'm fairly confident that it's the concrete walls and floors that are giving you issues with your bass. It possible that your room dimensions are an issue as well. Wayne is right, I would try room correction first. This would be the quickest and lowest cost solution.

Room treatments will likely net you the most gains. Check out GIK Acoustcs. They supposedly have free consultation services and are supposed to be extremely helpful. They sell a host of room correction products for very reasonable prices(no, I'm not an employee). I've been looking into room correction as well since my basement theater also has concrete walls and floors. I think your situation is far more problematic and challenging to resolve than mine but it sounds like a cool space.

Let us know what you implement and how it works. Hopefully the Moderator or other forum members have some other ideas as well.

Cheers,

T Cobe

Wayne, I've worked through the equalization and calibration side, and basically (as T Cobe suggests) I'm running up against the limits of the room itself. I can reduce or increase certain frequencies to balance out one very small area, but then I'm just magnifying the problem 2-5 ft away. I'm really impressed with these speakers when I'm in the right spot, but the room is working against me.

T Cobe, I had not heard of that provider and the website looks fantastic. My local shop had recommended some large and permanent acoustic treatments, and these look to be much more modular and doable given my space and its constraints. Will report back once I've gone through the process.

Appreciate all the ideas, everyone. Tremendously helpful!

Regarding your question in the first post regarding the use of a SubDude, or similar...I have been using Gamma's under my PB-13 Ultra, to great effect.

Cheers