What does a bad tweeter sound like?


Can anyone describe the sound....could it be louder than normal?
stringreen
Usually, it's no sound, rattling, rasping, or tizzing.

If you have one speaker that sounds a lot brighter, it is probably the other speaker's tweeter died. :)

Best,

E
If you have a capacitor short in the tweeter path, you may get a lot more mid/bass (a dangerous thing!)

If it is louder than normal, check your crossover. My experience has been either a crackling distortion or at certain notes you get a break up in the sound.
Whenever I "question" a drivers performance or simply want to conduct my own "test", I find that a 20 - 20Khz audio sweep is useful.
https://www.youtube.com/watch?v=PAsMlDptjx8

I've had crossover caps start leaking real bad and it sounded very much like the driver was blown, but only at very specific frequencies. It was also slightly louder. I was dealing with an AMT though. 
Thanks all....I just removed the tweeter from my Vandersteen 5A (left side) and am sending it back to Vandersteen for a rebuild.  I hear just as you describe...louder on that speaker, fuzzy and metallic on some frequencies.   I thought it was the midrange, speaker, but removed that one last month, got it back rebuilt, and the noise is still there.  I hope its the tweeter.
I'm not familiar with those speakers, but if the crossover isn't a real bitch to remove checking those caps out wouldn't be a bad idea. I doubt you have a leakage tester, but all the caps should measure up into the megaohms on a resistance test after a few seconds. Caps also tend to drift out of spec when the go leaky, but not always. Most of the leaky ones I've dealt with had drifted outside tolerance, but not all. They all failed to effectively block a few volts on a ohm meter though. 
I just found the 5A crossover. :) I would leave it alone unless you are already pretty well versed.

The 5A uses batter biased caps int he mid and tweeter sections. Pretty funky if you ask me. :)
Geez Stringeen ......I thought you had '' golden ears '' as you have proclaimed here after working in recording studios and you couldn't tell know if those older Vandersteen's tweeter is gone ? Maybe it is time to use them as door stops ......  
...just got the tweeter back and installed...just as I thought - the tweeters were checked to be working perfectly.   Vandersteen told me to check for tightness around the face plate....if not buzzing, then the only thing left is to check the crossover.   YUK.  This is no fun.
erik_squires....you probably know this, but the crossover and cables have a charge constantly going through them powered by a battery pack that gets changed every couple of years.  The idea is the same as Audioquest cables has. Its actually simple but not really elegant, since the batteries have to be hard wired in the amp, crossover, and high pass filter box.  ...done not often, but when all the batteries come back and installed after being run down a bit, the speakers have an new found clarity and power. It works.....
OMG that was fun huh? Problems with are systems really tests ones abilities. A good learning experience :-)
Go listen to Klipsch speaker, that's the standard .
Schubert...  standard for what???
Stringreen.  So do you think the tweeter problem is due to the exhausted energy of the batteries? I have a pair of Vandersteen Treo CT's with a 2Wq sub. I have the premium M5-HP crossovers which are required to run the sub in my system. I guess what I am saying is, am I going to run into this kind of problem when the batteries run down? What confuses me even further is the batteries have a 2019 exp. date from their factory and Vandersteen writes a 2022 exp. date on them with a sharpie. So is my battery life two more years or five???
Mr_M.....don’t think so, the batteries need to be changed in 2019 also (so marked)... Neither does Richard V. When the batteries exhaust, everything still plays, but with less dynamics, etc....it sounds like the speaker has to be broken in again. The difference is so gradual, you’ll never know there is a difference at all .. After battery replacement, within seconds it sounds pristine...... still sleuthing around.... I send the stuff to Vandersteen a bit before the batteries are due (the written in year that Vandersteen puts on them). Note that battery design has changed in the last years, so lithiums might be in your future. Don’t try to change the batteries yourself....its a ticklish soldering job.
Good luck. Can't have those Vandy's playing sub par!!