How bad is the damage to my speakers?


So I bought a Cambridge Audio Azur 851D DAC that can also double as a preamp. While hooking it up to my system (B&W CM10 speakers and Parasound A21 amp), I made a colossal mistake. While streaming music via my iPhone, I had the iPhone volume turned all the way up, and I mistakenly disabled the preamp/volume control section on the 851D, in other words the speakers started blasting at full volume. Obviously, I panicked and it took me at least 5 - 6 seconds to figure out what was going on before I could shut down the 851D. My ears are still ringing and I probably should get them checked out.

My question is how much has this mishap damaged the speakers? I've noticed that the bass is a bit looser since then and the slam is less obvious than before. Is this an expected result? What recourse do I have at this point? The speakers are only 3 months old. Does anyone know if the speakers have any built-in mechanism to protect against such stupid accidents? I'm just livid at myself right now.

128x128arafiq
I had a similar incident happen with a pair of B&W CM-7 Speakers using a new amplifier.
Stupid mistake but those CM's are some really tough speakers and I had no damage.
In the immortal words of the Terminator when Kate shot him in the mouth at the cemetary, "Don’t do dat." Repeat these words every time you are about to plug in your iphone without checking the volume.
Speakers are find, you would know almost immediately if you damaged them, blew them, etc...
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Hi all, I really appreciate everyone's feedback. The good news is that the speakers seem to be in good shape. I have listened to the tweeters with my ear against it, as well as tried gently pushing in the woofers. No problems there.

As for the reduction in sound quality, specifically base, I think it might have to do with the new Cambridge Audio DAC that I had bought brand new. After about 20 hours of use, the sound is improving. I'll probably let it burn in for another 30-50 hours before deciding whether to keep it or return it.

Again, I really appreciate the advice.
I agree will Dill's suggestion also, to check the woofers for any motion impedance. Also, put your ear close to each tweeter when playing. Most times power spikes fry a tweeter before they damage a woofer voice coil.
Hi!I agree with Dill ´s suggestion.If you hear or feel any scraping noise when spring them back, then there is damage, otherwise it´s all ok.Good luck!Raf
Nice speakers!

You probably did NOT do any damage at all. This is an excerpt from B&Ws marketing literature (for your model):

"Which means excellent timing and control, no matter how loud you’re playing it."

The specs for the speakers indicate recommend amp power is " 30W - 300W into 8V on unclipped programme" 


Your amp is rated at 25O Watt max into 8 ohm.

Unless you drove the amp into clipping there should be no damage. Extremely loud "normal music content" is fine. It might be worthwhile to run a frequency sweep through the speaker (at low volume mind you) to get a sense whether or not there is anything obviously wrong. Also, play some music you are already familiar with and volumes you are accustomed to and form an opinion.

Hope this helps. 




With your fingers in a spider pattern, gently push in the woofers and let them spring back out. Notice, is there is any scraping noise? You can either hear it or feel it. If you do, you might have a warped voice coil.
You may have just prematurely broken in your speakers, as over time the woofers tend to become less stiff.  Because it happens over time you generally might not notice the change. True damage you might expect from this event would have been a blown tweeter, and from your description that probably didn't happen.  Give it a few days and see if you get used to the sound before doing anything rash.