Speakers all come with various frequency ranges and its easy to see the change within a brand. For example, one speaker compay shows a bookshelf with a range of 55-20,000 Hz, another with 40-20,000Hz and once you move into towers, the range goes to, 35-20,000 Hz and even to 30-20,000 Hz. So the implication is that as you move up the speaker food chain, (in the same brand) the frequency gets lower on the one end. (sensitivity also goes up) But, when you look at a much more expensive speaker brand, speakers costing many times more actually list frequency ranges that would appear to be much worse! For exampe looking at Infinity's then Paradigms, and then Rockets, I can't see any consitancy with frequency range and price. Can sombody help me out with an explanation of why a speaker with a lets say, range of 60-20,000 Hz can cost 4 times as much as a speaker that has a 30-20,000 Hz rating? Given that impediance and sensitivity are almost the same. Any advice would be greatly appreciated.