I tried bass traps and room treatment which helped the sound overall but did almost nothing to help my 2 problem areas, one around 50 hz and another around 110 hz. I bought a used DSPeaker Anti-Mode 2.0 Dual Core here on Audiogon and it worked wonders at a reasonable price.
The X4 mentioned earlier is an even better option but cost substantially more. Good luck!
The X4 mentioned earlier is an even better option but cost substantially more. Good luck!