Help I think I blew a tweeter.

A couple of days ago I noticed the solo folk singer was coming out of the left speaker instead of the TV. After turning off the "Pure Direct," I put all the signal to one speaker and then the next. Sure enough the right speaker sounded all muddled with no treble. I've been experimenting with bi-wiring, so I disconected everything and reconnected. I opened up the speaker to see if any wires were hanging, there were none. I also switched speakers. The same speaker stayed muddled. I'm afraid I've blown a tweeter. I've never had the amp (80 wpc) up even to a third of the volume. The B&W 601's should have handled that OK. However, I do have a 17 yr. old son who uses the stereo before I get home in the afternoon. He's a drummer in a rock band.

Can you tell from my description what is wrong? If it's a blown tweeter, is that something that can be fixed, and would it be cost effective? Fortunately, I bought this first system on the cheap so I could experiment. I can afford a lot better if I have to. What do you think?