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?
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In my experience, B&W tweeters seem to "pop" more often than those found in other reputable brands. As such, your tweeter probably is "kaput". As you surmise, it probably was your son but no way to know for sure. Have mercy on him though as i remember being in a similar situation when my Dad had his system and i used to use it : )

With most of the earlier B&W's, one could simply swap diaphragms and be done with it. This is not difficult so long as you aren't a complete "fumble fingers" type of person. If you contact B&W and the speakers are still under warranty, they might even cover this.

My suggestion is to replace both tweeters at the same time. This will maintain a balance between speakers. Should you ever blow another tweeter, you'll have a spare that is already "broken in" similar to other that was left operational. Sean

PS... Sounds like your son needs a system of his own. My first "system" was probably the best gift i ever received. Then again, you can see where that led, so be careful... : )
Thanks Sean,

My plan is to tell my son if he can fix it (I'll buy the parts) he can have it. I wouldn't give him grief about it. I remember my days playing in a rock band in the 60's. He's no different, and he's a better musician to boot. It'll be a win/win situation. He'll get a stereo and I'll get to upgrade.
Sean, you really think B&W is going to give him a matched pair? Unless they STRONGLY allude to this possibility I'd just replace the one tweeter. Its surround will break-in eventually to match the opposite side. Sensitivity matching is more about # turns in the coil and gapping, no?
Ernie: No, i sincerly doubt that B&W would provide a matched pair, especially for a lower model. My thoughts are that this is probably not the last time that this will happen, so having a spare around would be worthwhile. Starting off fresh on both tweeters would pretty much guarantee even break in and that there were no "extenuating circumstances" should one blow again. If it did, Baileyje would have the spare that was already broken in, so the differences in drivers would be minimal.

Baileyje: While i can understand where you are coming from, won't this encourage your son to do minimal damage to your car, TV, etc... and then fix it so that he can have those too ??? : ) Sean
My old (decades ago) Magneplanars bit the dust because I blew out the tweeter wires. My new MG1.6 have a fuse, and the manufacturer claims to have proven, by practical tests, that it is impossible to blow the tweeter wires so long as the fuse is in place. Peace of mind!

It's a good thought about the car, tv, etc. The only problem is he's already done that. This is a smart kid, he probably did this to get the stereo.
Thanks for all the responses. I've ordered a new tweeter. However, I've got a couple more questions. Should I be able to see some kind of damage to the tweeter? I've taken the entire unit apart and I can't see any scratch or tear or even a dent. There are two very thin wires attached to the tweeter. They seem intact. Also, when I am playing music, I have gently touched the tweeter. It does not vibrate. I expected this, but the other speaker, which seems to work fine, does not vibrate either. I suspect I just don't know what I'm looking for. I thought I would feel a vibration on the good speaker. Any thoughts?
If you've got a multimeter or continuity tester, you can check to see if the tweeter is still conducting signal. Otherwise, you are not likely to see / feel a dome tweeter moving. You are talking about minimal excursion levels that are vibrating thousands of times per second. As such, the vibrations are SO fast and SO small, you aren't likely to detect them. Sean