B&W P5 Tweeter Problems and a solution...

Brett Flournoy

Posting so that someone in need might find this. I picked up a pair of B&W Preference 5's the other day for cheap, and in playing them against my Polk Rti 12's, they were getting kicked all over the schoolyard. It wasn't pretty. Turns out the tweeters were offline. No cheap fix either, B&W wanted $112 per tweeter, and repair seemed impossible. Fortunately their site had good detailed support info, plus I learned the issue was the ferrofluid would gum up over time, sticking the voicecoil in place. So I was able to remove, disassemble, repair and reinstall those suckers, work fine now, much more competitive!

Repair goes something like this: Rotate the faceplate with the help of the teeth, to counterclockwise about a half inch or so, it will be obvious when it is unlocked, then carefully pull on the tweeter cover to extract the unit from the cabinet. CAREFUL! Unplug. Now remove the clamp. You're now holding the tweeter assembly. CAREFULLY separate the two pieces, do NOT pull forcefully - that is the voicecoil in black and it's stuck in the gunk of the magnet (the problem). Once separated, you can now clean the gunk out of the magnet side to your heart's content, and here you don't have to be that careful (ever try to damage a magnet?). In fact, remove the top piece of the magnet (with the hole), clean all that crap out. A little oil won't hurt. Now, important.... you must center the magnets again, leaving room on the perimeter for the voicecoil to fit. This will take a little playing, but you don't have to be careful. Once done, reassemble, you're good to go! A completely renewed B&W P5 or B&W Preference 5 speaker system.

Skogsguden

I have the exact same problem, with the exact same speaker.

How are your speakers playing after the tweak? Do you have any problems with heat in the tweeterunits after you removed the cooling ferrofluid?

Tebirkes

snip 8< I learned the issue was the ferrofluid would gum up over time, sticking the voicecoil in place. So I was able to remove, disassemble, repair and reinstall those suckers, work fine now, much more competitive!

... the voicecoil in black and it's stuck in the gunk of the magnet (the problem). Once separated, you can now clean the gunk out of the magnet side to your heart's content, >8 snip

First, thank you thank you thank you for relaying this tip from B&W's website! Excellent description of the procedure and quite easily accomplished. I must add that my tweeters didn't have "ferrofliud/gunk", but lots of iron filings that were "gumming up" (restricting) the full movement of the voicecoil. Unless "ferrofluid" is what you intend to describe fine iron filings as. And I didn't use oil - don't want my speakers smelling like french fries or cycle chains.

Will report back on hot tweeters if they occur. Best guess would be friction between the voicecoil and the magnets, for magnets not quite back in their proper place. I used a std unfolded paperclip to ensure the same gap size all around the replaced magnets. A small enough Philips screwdriver would also work.

Cheers,

zingo

I've fixed a few B&W tweeters and many of them disassemble very easily. Had someone push in an aluminum tweeter, so I took it apart, and careful pushed the dome back out until it looked almost new; very serviceable.

davidboyd

This is a useful topic, but, in reference to "here you don't have to be that careful (ever try to damage a magnet?)" – you do have to be very careful of magnets like this because they are brittle and easily damaged. The easy damage is bits getting chipped off the brittle magnet edge, but worse has just happened to me as I was completing this repair. After disassembling the magnet and casing to do a thorough clean, which was difficult as all the gunk is magnetic and sticks resolutely to the magnet and steel, I was putting the magnet back in to the case, when it slapped in, pulled by the strong magnetism. The shock split the magnet in two. There is no way of repairing the magnet, in fact the two broken halves now repel each other, so that's the end of this repair.

**If anyone has a broken tweeter they don't want to repair, I would be glad to have it in order to salvage the magnet.
Good luck.

flowergrower

Worked for me too! I can't thank you enough dude!

funk_tschway

hey just for anyone who's going to be doing this at some point in the next 5-10 years and while this content is still the search result to how to fix a tweeter i have some advice:

you DO have to be careful if you want to take the magnet out. there's another page elsewhere with a broken magnet if you do some research. while putting it back in, the magnet has a tendency to try to snap in place and can sometimes break. YOU DONT WANT TO break the magnet as you might not be able to find a good replacement with the right size in your area - but you can basically just get a new neodymium magnet with the exact size.

also, some sources say that you dont need to take the magnet out. well i did not take my magnet out of my z3123 tweeters for the p4 (and also p5,p6?) and just did the masking tape clean-out. now when im listening to certain songs with high frequencies I can still hear some crackling. I believe this is because I moved the magnet around a bit during the clean up and some old ferrofluid seeped right under the magnet itself in tiny amounts. so next time when i'm feeling so inclined i'll redo the whole thing and actually take out the magnet and clean the whole thing. if you want to do this MAKE SURE YOU MARK THE POLARITIES - as in make a mark on the magnet and then go right above it onto the housing ring and make a mark there too. this is how you should put back the magnet after cleaning.


hi mom!

xschop

I passed on a nice set of B&Ws recently after seeing all the tweeter issues posted various sources. At least with Polk you can still get factory tweets without paying via appendages.

F1nut

Tebirkes wrote: »

snip 8< I learned the issue was the ferrofluid would gum up over time, sticking the voicecoil in place. So I was able to remove, disassemble, repair and reinstall those suckers, work fine now, much more competitive!

... the voicecoil in black and it's stuck in the gunk of the magnet (the problem). Once separated, you can now clean the gunk out of the magnet side to your heart's content, >8 snip

First, thank you thank you thank you for relaying this tip from B&W's website! Excellent description of the procedure and quite easily accomplished. I must add that my tweeters didn't have "ferrofliud/gunk", but lots of iron filings that were "gumming up" (restricting) the full movement of the voicecoil. Unless "ferrofluid" is what you intend to describe fine iron filings as. And I didn't use oil - don't want my speakers smelling like french fries or cycle chains.

Will report back on hot tweeters if they occur. Best guess would be friction between the voicecoil and the magnets, for magnets not quite back in their proper place. I used a std unfolded paperclip to ensure the same gap size all around the replaced magnets. A small enough Philips screwdriver would also work.

Cheers,

I realize this is a very old post, but the poster has no idea what he's doing. You have to replace the ferro fluid.....geesh!!!

dhad06

I realize this tread is old. But can anyone verify, that on the B&W P5 you twist the tweeter casing about an inch counterclockwise to unlock.

I've tried this, but only cracked a nail doing so... :-(

Cheers Peter

dhad06

Okay, cleaned my tweeters out this morning. Took nearly an hour to clean out the first one, but only about 15 minutes from the second one. Wooden toothpicks, although snapping all the time, really did the difference.

Please observe that the above method is for the P6, not the P5. The P5's doesn't need twisting, but can be pulled straight out by using your nails or a knife.

The tweetets come apart as shown in this picture courtesy of www.loudspeakerrepair.com.



Cheers Peter