Hi, I'm an absolute beginner to this site and relatively new to home cinema, apart from one box solutions but I guess they don't count. Recently purchased some mission 773's second hand and have been unable to get any bass from them. Tried them on two amps, bi-wired and normal and still no bass. Plenty of mid-range and treble. I assume the bass drivers are blown? Does this sound right? The speakers have two drivers that seem to handle mid range and bass, the mid range is coming out ok but with no bass? I have found some replacement drivers for the speakers (correct mission ones), would this be the best route to fix them? Thanks very much for any advice.