Help with blown tweeters/power issue


All,

Last night I was happily listening to my new speakers - the largest audio purchase I have or ever will make - when my amplifier’s display  blinked on and off, AirPlay cut in and out, and then wham - the volume jumped up to max with no input from me.  
I immediately shut off the amp, but I fear the damage is done.  The speakers and amp still make sound, but all I hear from the tweeters is a soft, high-pitched hiss. I assume they are blown, and I have no idea what else could be wrong inside the cabinets. 
I have no idea what happened.  My only thought is that the dryer was on nearby and could have caused some sort of voltage spike to the amp.  When I turn on a nearby dehumidifier the lights dim momentarily, which makes me suspicious there is some power issue at play.
I have two questions:

1. What do I need to do to assess the full extent of damage to the speakers?  There are no dealers nearby. 2.  How can I prevent this from happening again?

Thanks for any help.  This has been an awful experience. 
128x128lousyreeds1
1. What do I need to do to assess the full extent of damage to the speakers?

Most likely the voice coil got hot enough to deform or burned enough insulation to get stuck in place, which is why it makes only soft sound, but not hot enough to completely burn out, in which case it would be dead silent. To assess this remove the tweeter and hook it up directly to the amp. Full range will not damage a tweeter, if the volume is low, so if it is still good you will know, it will sound like its getting a full range signal. In that case its crossover damage. Which is unlikely. Almost certainly the tweeter. But you asked how to assess. This is how you assess.

The tweeter will probably be marked with a part number or something. Do a search, locate the replacement, swap em out. No big deal.

Given how new it is and what happened you might also try calling the manufacturer. Honestly explain exactly what happened, throw yourself on the mercy of the court. They may offer to send you a replacement. Or let you buy one from them. At the very least they will probably help you find the correct replacement.

You don’t mention the speaker, or anything. Just so you know, a lot of the higher end speakers use matched drivers. So when you call be prepared with serial numbers, parts numbers, purchase details, etc. Manufacturers have a lot of clueless customers. They make their policies accordingly. That’s why more often than not they require you ship the whole thing back. Like you can’t turn a screw-driver. Because frankly, many cannot. The more you appear to know what you’re doing the more likely they are to send a replacement, which would be my Plan A.

There are no dealers nearby. 2. How can I prevent this from happening again?

Only way to truly prevent this is to fuse the speaker or tweeter. But I don’t recommend it. Much better to learn your lesson: avoid digital. Nothing good ever comes of it.
No idea if your speakers or amp are blown.  I'd get a cheap pair of speakers and try them.

I suspect it's either your amp OR your amp and your speakers.

It's also difficult to tell if you have merely surges or surges and sags. You may be one of the few people who actually needs voltage regulation.  Get an inexpensive voltage meter to see how low your V gets.

https://amzn.to/34oDw4I

I strongly recommend ZeroSurge, or Furman power protection. 

Best,

E
Miller makes a good point in that you have not mentioned the make of speakers, or amp.
I know for sure that in some earlier Wilson models the resistors in the crossovers usually blew well before damage to the mids or tweeters, please do NOT ask how I know this fact....lol.
And if you have ever had to tip a 220lb speaker over to remove the bottom panel to access the crossover panel you realise it is not something you ever want to repeat!
I am sure Wilson were not alone in this and as you say they were your most expensive purchase.

I am assuming from your post that you have no surge protection or line conditioner in place, although not 100% sure if they would have prevented the amp doing what it did but could well have.

I can only imagine just how distraught you must be at this stage though, always sorry to hear of audio tradgedy.
Agree with miller, call the manufacturer. Some are really nice and may do you a big favor as well as giving advice to avoid it happening again.

Miller- What do fuses have to do with digital? 
Silly two cents worth, Fuses? don’t suppose there is a fuse problem anywhere?

Maybe you’ll get lucky, with the fuse.

NOW, protect the expensive gear, no matter what anyone says.
You choose a good product, others will chime in.. Best of luck..

Regards
If you hear a hiss in your tweeters they are still working. A bad tweeter will generally give you no sound at all. The failure mode you mention is really unusual. An amps volume does not go through the ceiling without help from something, a tripped switch to a program source with more gain. You can get a test CD with a frequency sweep that will tell you instantly if any of the drivers are blown.
You could put a surge protector on the system but I am not so sure this was a power issue. 
All,

Many thanks for the insight. 
If you hear a hiss in your tweeters they are still working. A bad tweeter will generally give you no sound at all.
If I'm hearing a hiss through the tweeters but no other sound, what does that mean for likely damage?  The crossover?  Something is clearly wrong.  
To assess this remove the tweeter and hook it up directly to the amp. Full range will not damage a tweeter, if the volume is low, so if it is still good you will know, it will sound like its getting a full range signal. In that case its crossover damage. Which is unlikely. Almost certainly the tweeter.
I'll try this tonight.  
You could put a surge protector on the system but I am not so sure this was a power issue.
Everything was plugged into a surge protector.  It very well may not have been a power issue, but I can't imagine what else could have caused this.  The amp now appears to be working completely fine.  

All,

For those who enjoy a bit of humor or schadenfreude, here's where this turned out.  

I was able to recreate the problem, which as some of you suggested, had nothing to do with power issues.  It was a simple network glitch with AirPlay - I had held down the volume up button on my phone for too long when it didn't initially respond, and when it did, it skyrocketed to max volume.  A simple app update solved the problem.

And having run a number of frequency sweeps on the speakers and played a lot of music, it appears the woofers, tweeters, and everything else are in fact fine.  No harm done.  The hiss from the tweeters is just a bit of AC noise.  

So this was a network malfunction combined with audio nervosa on my part - all is well.