Hi. My (stereo only) sound system uses a pair of Klipsch RF-7 MKII speakers, which have rear bass ports. Right now my listening space is arranged so that the speakers are set against a brick wall behind which there is just the street. However, the space is very poorly used, and I'd like to rearrange things so that the speakers are against a wall (double drywall, some insulation) which I share with my neighbors. I'd like to keep my neighbors happy, and my bass pumping. If I use sound-insulating foam I lose the bass. Is there something that will reflect those lower frequencies while sparing my neighbors? Thanks!