These speakers sound tinny and weak

I knew what I was getting into buying a pair of $14 speakers, but it turns out I can't take it--I'm going to return them tomorrow for a refund.

I listen to all sorts of music, from contemporary pop and r&b, to alternative, to classical, to spoken word and performance. The only things that sound good are spoken pieces. Anything else sounds like you have a pair of headphones turned up really, really loud and you're trying to pass them off as real speakers.

I'm in a room roughly 12x12 feet, and the sound doesn't fill the space.

The same company makes a different model that includes a subwoofer for only $5 more, but I really didn't want to deal with a subwoofer block. I just want a simple pair of PC speakers that sound as good as my roommate's set, which are JBL models from about five years ago. Looks like I'll need to save up more than $20.