Blown Woofers in Matrix 802 S3


I have a quetsion I hope someone out there can help me with! I have a pair of B&W Matrix 802 S3 speakers driven by a Musical Fidelity M3 Integrated Amp. Has worked very well for many years. Source used to be MF 3D CD Player but now is computer based via a Logitech Duet to a Benchmark DAC 1 and into the amp. About eight months ago the lower right side woofer started making a scratching sound - I assumed it was blown/damaged from old age and replaced it with a new one from B&W. Problem fixed - or so it seemed. Just yesterday the new woofer on the lower right hand side has developed a similar scratching sound. My question is this - what is the likely root cause of this? Given the other three 15 year old woofers are working perfectly yet the new one has developed the same problem as its predecessor. Could this be caused by an ageing crossover? What else should I look at/test to find the root cause before once agin replacing this woofer? Luckily I bought two woofers at the time - one for insurance - as I really do love these speakers - I just do not want to have the same thing happen to it! Any help or guidance you can provide is much appreciated.
david_doerfer
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I bet let's say quite a-bit that if you swap your speakers, you'll get another lower woofer blown(don't have to do that for test tho) and the problem is with amp's right channel draining DC onto speaker. Don't swap your woofers -- no point.
I'd bet, as well, that if you switch your right lower speaker driver it will blow again. I'm pretty sure its not your amp, though. I had the exact same speakers. I bought them new, when they were current. My best friend bought the same exact speaker because he liked mine. My friend that works in the audio store had the same exact speaker. The store I bought them from had 2 brand new pairs on display. (One pair in a 2 channel setup and the other and the other was in a theater.) Every single pair of speakers I just mentioned had the right lower driver go bad. To this day no one can figure out why they went bad.

I was able to come up with the most plausible theory as to what was going on. Understand, though, I may very well be wrong and that this is just my best guess. The only thing common to all 5 pairs of speakers, besides the fact that they were all the same exact model, was the demo music. We all used many of the same CD's. Either we each owned our own copy or we lent each other some albums. I figure that there was something on one of the CD's, like a certain note or sound comming from right channel, that the speaker just did not like. Maybe a crossover point or a weakness in some of the material. Your guess is as good as mine. That's the best I can come up with.

I know that you are going to ask me what CD's we were using. We never figured out which one it was (If it even was one of the CD's to begin with.) There were well over 50 CD's that we had all used. Also, it was a long time ago and I know I can't remember them all.

Sorry that I couldn't give you more info but maybe something I brought up can lead you in a direction that my friends and I overlooked.
Zd, Why then right? How do you know? Are speakers and drivers marked with labels and they're in fact different?
To my understanding if you swap speakers, Left becomes Right and when Left becomes Right will it have blown woofer or it won't?

If it's common B&W problem, tickle their nerves about free replacement or replacements up till it works continuousely. Play music non-stop when you get replacement one. If they refuse to replace woofer, charge-back your card.
Marakanetz

Sorry, I forgot to put this in my post. The speakers are not marked left and right. So, yes, if you move the left speaker to the right, it should still blow the driver. Honestly, though, I can't remember if any of us actually tried it.

As far as warranty goes, the 802 s3 was discontunied in the mid to late 90's; probably 97-98. I doubt that B&W would warranty something that old.
#1 They should warrant the woofer at least.
#2 If left would move to the right and get blown, than it's even more the fault of amp right channel.
Marakanetz

As far as #1 goes, don't hold your breath. B&W's customer service is terrible when it comes to things like this. I moved a few years ago and brought along a pair of B&W speakers that I had for only 2-3 months. There was no local dealer in my new location, so I asked them if they could just send me the part (crossover)and I would install it myself. Offered to send them the old crossover, as well. Anytime B&W hears the words shipping or mail, they go nuts. To make a long story short, They were kind enough to sell me a new crossover at full list and I had to drive over 100 miles to pick it up at a dealer. They made it very clear that they were doing me a big favour.

Looking at your #2, I really don't think it was the amp. In order to consider the amp as the cause, It would have to be used on all 5 pairs of speakers. I know for a fact that there wasn't one amp that went on all 5 pairs. Even if it did, how do you explain the same thing happening David_doerfer's pair? For me, at least, 6 pairs with the exact same problem, is beyond chance. There is also one other thing to consider with regards to the amp being the source of the problem. The amps that were used with the 802's were also used with many other speakers with no problems. That's why I though it might be one of the demo CD's. Its the only I can think of.

I would be glad to believe statistics and patterns, but the word 'right' kinda freaks me.
Glad I've never liked any of the Bowers. Aerial sent me a replacement woofer with 1 year warranty... Love'em my 10t's.
David,

I know this thread goes back a couple of weeks- but where did you source the woofers?
It was my understanding that B&W themselves no longer have inventory, and I found a specialty audio shop up in CT. or Mass that sells them for like $340 plus shipping. Did you find them for less?

I don't need them- YET- but two of the four have started to develop the classis B&W "wrinkle" in the suspension which I have seen in a LOT of their woofers from that period. The specialized shop I called said it has little/ no effect on the woofer sound, but it likely need replacement down the road- and I push them pretty hard. I actually love them and believe the sound is different and much more musical then the bulk of their speakers. Probably, along with the classic 801's, the most musically enjoyable speakers B&W ever made. IMO.

Thanks. Gary