Could someone explain speaker specifications to me?

i wouldn't pay a whole lot for those. 15 watt sub isn't much and 10 watt satellites isn't much either, they will work and sound alright but if you are wanting booming b and ultra clear and powerful speakers overall, those won't do it. $20-30 is all i'd pay for those, at the most. 48hz is the low end, how deep the b gets, and its not very low.