Help with capacitor

[Opus007]

Can anyone recommend a replacement capacitor for the one in the picture.I do not have the ability to test to see if it bad.
Here is my problem and what I have done.Replaced all speakers in the B&W 685 speaker boxes.Replaced inductors in both boxes.My problem is one speaker sounds lower in volume than the other.After playing music for awhile the speaker box that is giving me problems all of a sudden pops into place and all sounds good.I thought maybe it is the amp or cd player but used a different amp and cd player.I thought it was a bad speaker and ended up replacing all them.I replaced the inductors... still the same problem until it has played for awhile and then it pops into place.

I am not all that technical when it comes to capacitors and what little I have read indicates that the capacitor builds a charge inside of it.For what I do not know.

I have ****** (excuse my french) with repairing these for 3 months now.Waiting for speakers to burn in and long hours of listening and saying ...what the heck(not in those words)just down right irritating.ARRGGGG!

So would a capacitor gone bad or going bad cause what I am experiencing?
B&W has been very good to me and has sold me all drivers at half off.These speakers where returned to me from a sale where the buyer made slinkies out of the inductors and then returned them to me.I tossed them in the garbage but had second thoughts and retrieved them.Since then I have been on this journey.

If it is the capacitor in one then I guess I should just get replacements from B&W.Unfortunately you can not buy just the capacitor but have to buy the whole crossover board assembly.May have to just do that in the end but am looking for some help on if it could be a bad capacitor.
Thanks.
Shaun

Ahhh I feel better already after writing my frustration....

[NickS]

http://www.parts-express.com/pe/showdetl.cfm?Partnumber=027-419

Could be something as simple as a bad solder joint on the crossover board.

Try gently wiggling each individual crossover component on the board while the speaker is playing and see if you can recreate the problem.

[mjb]

Are the drivers free moving? The pop then normal volume isn't mechanical?
Inductors don't usually fail, if they do, they mostly go open circuit.
Capacitors might change their value, but again its rare, they'll usually go open.
More likely its a dry joint or a hairline cracked track on the PCB, these can be frustrating and hard to find. Have you tried flexing the board, or pushing in various area's, to see if you can make the sound change? Have you re-soldered every joint? Ohm checked between components on the same track?
If you do want to change the capacitor, notice that its non-polorised.
Good luck!!

[Opus007]

I re-soldered all the the solder joints and checked the board for cracks with a magnifying glass earlier today.Nothing is loose on the board.Hmmmm.Just can not figure it out.

[Opus007]

Are the drivers free moving? The pop then normal volume isn't mechanical?
Inductors don't usually fail, if they do, they mostly go open circuit.
Capacitors might change their value, but again its rare, they'll usually go open.
More likely its a dry joint or a hairline cracked track on the PCB, these can be frustrating and hard to find. Have you tried flexing the board, or pushing in various area's, to see if you can make the sound change? Have you re-soldered every joint? Ohm checked between components on the same track?
If you do want to change the capacitor, notice that its non-polorised.
Good luck!!

It doesn't go pop,I was just saying it seems to pop into place.I have not pushed on the xover board when playing music as each time I have done something I put it ll back together before listening again.

[NickS]

Does the unit have a resetable fuse such as a Polyswitch type.
These components normally look like a ceramic disc capacitor and are basically a non linear thermistor.
If one is out of spec it could be attenuating the signal when its cold and then allowing it to pass when it warms up.
You could actually short across it's leads to see if the problem disappears.

[Opus007]

Does the unit have a resetable fuse such as a Polyswitch type.
These components normally look like a ceramic disc capacitor and are basically a non linear thermistor.
If one is out of spec it could be attenuating the signal when its cold and then allowing it to pass when it warms up.
You could actually short across it's leads to see if the problem disappears.

There are only 2 things on the crossover board.A inductor and capacitor.Nothing else is in line to the speakers.

[NickS]

Try swapping the capacitors on the crossovers between the good and bad speaker to see if the problem follows it.

[Opus007]

Try swapping the capacitors on the crossovers between the good and bad speaker to see if the problem follows it.

After further testing I decided to pull my rear surrounds and place them as the mains on the receivers b channel so I could a/b speakers for differences. What I found was I can not tell a real noticeable difference.Maybe the B&W speaker on the right side has a little less pronunciation of the tweeter. I did drop the tweeter when I was installing it (new) so it took about a 3 foot fall from the table.And I do have another replacement tweeter coming and it should be here on Monday.

When a/b testing separation sounds identical.Some tracks play more to the left and some more to right and others pretty much both sides so both sets of speakers where separating the music identically.

So I pulled my bedroom speakers and same results.So maybe I damaged the tweeter and thus the softer highs on the right side.But ...I have swapped left to right and right to left so many times that by the time I swap them I am unsure of what I am hearing.

At this point I do not want to un-solder the capacitors until I get the new tweeter.Also I have moved the tweeter to the other speaker box and have done this several times but by the time I get the speakers put back together I am unsure if it makes a difference.At times I would say yes and then say no.

Oh what fun trying to finger this out...

Below is the reason I am repairing these speakers as this is how both crossovers where when I got the speakers back.

[lhwidget]

Hi Nick,
That was a nasty buyer for sure...

The cap in your picture is an odd value. It isn't an uncommon capacitor type, but 4.7 µF is the common value, not 4.3.

You could get a 4.3 µF value by installing these two caps in parallel. They aren't MKP types, but are rated for 250 VAC and will work fine.

They won't fit properly, but you can install them up off the board with insulation on the long leads if needed. These are axial lead caps, just twist and solder the leads together, then insert the leads into the holes where the original cap was installed.

http://www.parts-express.com/pe/pshowdetl.cfm?PartNumber=027-222

http://www.parts-express.com/pe/pshowdetl.cfm?PartNumber=027-210

[Opus007]

OK, got the new tweeter today and it made no difference so I removed both capacitors and the one I was thinking was bad is the one in the attached photo.Notice it has a small hole in it that is about 3/16 deep and another smaller one that's about 1/16 deep and looks to be caused by heat.The other capacitor does not have these defects.How it happened I do not know and not sure that the small holes have any bearing.

So I swapped capacitors and now the lack of highs has gone to the other speaker.What really seems to be happening is some of the high frequency seems to be rolled off.Also there is no real extension with the highs where I put this capacitor.

The caps that you guys gave me links to seem to be pretty cheap and am wondering if there are any better caps out there ?Also it says 200 vac.Does it matter is the vac is a higher value.

Thanks for all the help so far.

[lhwidget]

The higher voltage won't affect the performance, but they will handle higher signal levels.

You can look through Madisound's and Parts Express' web sites for fancier brands if you really want to spend more

I'm not a big fan of boutique caps and equipment, but I do look for high performance in what I buy. I think the high tolerance line of poly caps from PE is one the best bargains around. Also, for every person like me, there is someone who will swear by the fact that some of the more expensive caps sound better. Since you're in a good position to experiment, you might want to try comparing both the cheap and expensive caps in the same speaker.

http://www.madisound.com/index.php

[Opus007]

Are the drivers free moving? The pop then normal volume isn't mechanical?
Inductors don't usually fail, if they do, they mostly go open circuit.
Capacitors might change their value, but again its rare, they'll usually go open.
More likely its a dry joint or a hairline cracked track on the PCB, these can be frustrating and hard to find. Have you tried flexing the board, or pushing in various area's, to see if you can make the sound change? Have you re-soldered every joint? Ohm checked between components on the same track?
If you do want to change the capacitor, notice that its non-polorised.
Good luck!!

How can you tell from the picture that it is non-polarized?

[NickS]

All passive crossovers use nonpolarized capacitors.
Polarized capacitors have their polarity marked near one of their wire leads with either a + or - symbol.

[BOBinGA]

Judging from the picture of the inductors and the latest picture of the cap, it looks like the old owner said to himself, "Gee, I wonder what would happen if you plug these into the wall outlet? I always wanted to hear what 60 hz sounded like." Now you know how the coils turned into Slinkys. Just be happy that the woofer still works at all.

The first cap Nick linked to will do fine as a replacement. In fact, you won't find a closer replacement than that.

-Bob

[Opus007]

All drivers and inductors have been replaced with new ones.Only thing left is either the capacitors or the pcb board itself.I think since B&W is giving me 50% off and I have replaced most everything so far the way to go is to just buy the crossover board and that way I have the right capacitors and inductors and new pcb boards so the units will be completely rebuilt with all the original parts.Cost is 104 per crossover board( with inductors and capacitors) and 1/2 off I will get 2 for 104.And that eliminates any further problems as all will be new.

[lhwidget]

True, but the cap Nick linked to will get you going for just a few $.

Sorry about the confusing link to a second solution, I didn't see his post, and I didn't look as hard as Nick

[Opus007]

Thanks for the help.I just got a email from B&W as I sent a picture to them of the capacitor I removed and he said he can send me just the capacitor if that would help.

I must say B&W has gone out of there way to help me even though due to selling these speakers they are out of warranty.