Most apartments are made like crap with little insulation, let alone any sound proofing. As folks have pointed out here getting things off the floor will help, but my experience has been that certain types of speakers are just not apartment friendly. Yours maybe one of them. Elizabeth found that Maggie's (and headphones) do the job for her. For me it was a pair of Quad's. Both provide great sound and just the right amount of base. In the Quad's case the technical limits on volume become a positive for apartment life. I'm running the Quad's with a 20 watt tube amp and love the result. Consider changing your speakers first. If that doesn't work and headphones are not an option- as much as it going to suck moving might be the best thing to do.
Good luck
Good luck