B&W Capacitor Replacement- Need Help - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 22nd January 2011, 12:40 AM   #1
diyAudio Member
 
Join Date: Jan 2011
Default B&W Capacitor Replacement- Need Help

Hello everyone

My father gave me a pair of B&W P-4s a few years ago. They have been great to me until recently the tweeter stopped working in one of the speakers. I am somewhat tech-savvy (I mainly work on cars) so I opened up the back and used a multi meter to narrow the problem to a faulty capacitor. I was reading a previous thread about replacing the capacitors and I really don't know what to do here. Order a replacement or upgrade to increase my sound quality?

The capacitor reads:

BENNIC
Bi-Polar
10 MFD
70 WV

I appreciate any help. Thank you.
  Reply With Quote
Old 22nd January 2011, 01:08 AM   #2
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
With a 10 uF cap, you should look to replace both with poly caps. If there are any other caps in the tweetr leg of the XO, i'd put poly in there too.

Post a picture?

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 22nd January 2011, 01:41 AM   #3
diyAudio Member
 
Join Date: Jan 2011
Click the image to open in full size.

I thought I had it narrowed down to a capacitor based on continuity but I noticed that the other capacitor doesn't have continuity either and that speaker works...

There is NOT continuity between the terminals and the wire that goes to the speaker though. The red one to be specific. So it is something in this board. Any ideas here?
  Reply With Quote
Old 22nd January 2011, 02:14 AM   #4
diyAudio Member
 
Join Date: Sep 2006
Location: New England
You don't have continuity thru a capacitor like you do thru resistors and coils. In order to check caps, you need an ESR and/or an LCR meter.
  Reply With Quote
Old 22nd January 2011, 02:28 AM   #5
diyAudio Member
 
john dozier's Avatar
 
Join Date: Dec 2010
Location: columbia sc
Check the resistance of the tweeter voice coil.Do this on both the working and non working tweeter. They should be the same If not, you will need a replacement diaphragm for the bad tweeter. Hope this helps
  Reply With Quote
Old 22nd January 2011, 03:47 PM   #6
diyAudio Member
 
Join Date: Jan 2011
I don't think the issue lies in the tweeter. I don't have continuity between the terminals and the speaker wire for the bad tweeter but I DO have continuity for the rest of them. See this pic. The problem has to lie somewhere on the board.

Click the image to open in full size.
  Reply With Quote
Old 22nd January 2011, 04:38 PM   #7
diyAudio Member
 
Join Date: Apr 2003
Location: Portland,Oregon
Blog Entries: 4
Send a message via AIM to DigitalJunkie
The capacitor is likely to be in series with the positive tweeter wire,Normally you won't have continuity there because capacitors do not have continuity between the leads (at DC anyway).
The caps are probably okay,but it couldn't hurt to replace them with some film caps or something,as Dave mentioned.

Test the tweeter voice coil with your DMM,and make sure it isn't an open circuit,if it is,it's toasted.
  Reply With Quote
Old 22nd January 2011, 06:22 PM   #8
diyAudio Member
 
Speedskater's Avatar
 
Join Date: Sep 2002
Location: Lakewood, Ohio
If your DMM has a low voltage AC range, use some high frequency test tones and measure both the good and bad channel.
__________________
Kevin
  Reply With Quote
Old 22nd January 2011, 09:22 PM   #9
diyAudio Member
 
Join Date: May 2010
Default Go around the crossover

All the crossover does is let the right band of audio frequencies get to the tweeter. You can test the speaker by driving it direct from your amp. Keep the volume very low. It's unlikely the fault is in the crosover.
  Reply With Quote
Old 23rd January 2011, 05:47 PM   #10
diyAudio Member
 
Join Date: Jan 2011
Quote:
Originally Posted by harryglan View Post
All the crossover does is let the right band of audio frequencies get to the tweeter. You can test the speaker by driving it direct from your amp. Keep the volume very low. It's unlikely the fault is in the crosover.
Did the test. Looks like I have a bad tweeter

So how should I go about finding one and replacing it? I haven't torn into a $300 speaker before and I'm a little nervous about this.
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Please Help with capacitor replacement hearingisbelieving Solid State 3 3rd December 2009 11:36 PM
Capacitor Replacement in a Guitar Amp betelgeuse Parts 11 7th July 2009 05:36 PM
Capacitor Replacement - HELP PLEASE! SoundQuest Solid State 1 2nd April 2008 12:36 AM
Capacitor replacement bulgin Solid State 11 2nd August 2006 09:08 PM
Capacitor Replacement on Spectro Amp ralph-bway Solid State 2 17th October 2003 03:52 AM


New To Site? Need Help?

All times are GMT. The time now is 09:02 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2