Go Back   Club Bazooka > Bazooka Technical Forums > Amplified Tube Subwoofers

Notices

Reply
 
Thread Tools Display Modes
  #1  
Old 06-25-2011, 10:36 AM
sjgrall's Avatar
sjgrall sjgrall is offline
Just Gettin Started
 
Join Date: Jan 2008
Location: Upperco, MD.
Posts: 7
Thanks: 1
Thanked 1 Time in 1 Post
Groans: 0
Groaned at 0 Times in 0 Posts
Reputation: 1
sjgrall is an unknown quantity at this point
Default T62A-40 Crossover Issue

Hello,

I have an original T series T62A-40. I replaced the electrolytic capacitors last fall, and saw a substantial sound quality improvement. However, recently, the crossover is not working correctly; at nearly any position, 60-75 Hz is at a lower volume than the rest of the 40-100 Hz range. The only way around this is to set the crossover almost at 250 Hz, which is less than ideal. Does anyone here have any idea which component on the amp to troubleshoot? I'm thinking one of the replaced capacitors may be failing prematurely, but I don't want to replace ALL of them again, and they look fine visually. I've also tried cleaning the level and crossover potentiometers. The 4 year old WF641.5 replacement woofer has a very small crack in the surround, but I don't think that would cause this type of issue….

I ordered a new BTA6250D to replace it, but I'd hate to throw the antique away when it may be something simple to repair, and then perhaps I could put it on eBay.
Reply With Quote
  #2  
Old 06-25-2011, 10:53 AM
heavyduty's Avatar
heavyduty heavyduty is offline
Super Moderator
 
Join Date: Jan 2008
Posts: 2,952
Thanks: 351
Thanked 771 Times in 690 Posts
Groans: 0
Groaned at 0 Times in 0 Posts
Reputation: 781
heavyduty is a splendid one to beholdheavyduty is a splendid one to beholdheavyduty is a splendid one to beholdheavyduty is a splendid one to beholdheavyduty is a splendid one to beholdheavyduty is a splendid one to beholdheavyduty is a splendid one to behold
Default Re: T62A-40 Crossover Issue

Quote:
Originally Posted by sjgrall View Post
Hello,

I have an original T series T62A-40. I replaced the electrolytic capacitors last fall, and saw a substantial sound quality improvement. However, recently, the crossover is not working correctly; at nearly any position, 60-75 Hz is at a lower volume than the rest of the 40-100 Hz range. The only way around this is to set the crossover almost at 250 Hz, which is less than ideal. Does anyone here have any idea which component on the amp to troubleshoot? I'm thinking one of the replaced capacitors may be failing prematurely, but I don't want to replace ALL of them again, and they look fine visually. I've also tried cleaning the level and crossover potentiometers. The 4 year old WF641.5 replacement woofer has a very small crack in the surround, but I don't think that would cause this type of issue….

I ordered a new BTA6250D to replace it, but I'd hate to throw the antique away when it may be something simple to repair, and then perhaps I could put it on eBay.
The potentiometer would be the first component to check. If that is not the problem, you are then looking at the active filter on the board.
__________________
power your system down
Reply With Quote
  #3  
Old 06-25-2011, 11:11 AM
sjgrall's Avatar
sjgrall sjgrall is offline
Just Gettin Started
 
Join Date: Jan 2008
Location: Upperco, MD.
Posts: 7
Thanks: 1
Thanked 1 Time in 1 Post
Groans: 0
Groaned at 0 Times in 0 Posts
Reputation: 1
sjgrall is an unknown quantity at this point
Default Re: T62A-40 Crossover Issue

I'm by no means privy to all that goes into an amplifier's design. What components make up the active filter, and where might I find replacements for those components, as well as another compatible potentiometer?
Reply With Quote
  #4  
Old 07-08-2011, 10:52 PM
sjgrall's Avatar
sjgrall sjgrall is offline
Just Gettin Started
 
Join Date: Jan 2008
Location: Upperco, MD.
Posts: 7
Thanks: 1
Thanked 1 Time in 1 Post
Groans: 0
Groaned at 0 Times in 0 Posts
Reputation: 1
sjgrall is an unknown quantity at this point
Default Re: T62A-40 Crossover Issue

For those who are curious, the issue was traced to the crossover potentiometer itself. I was able to resolve the issue with Deoxit Fader products.
Reply With Quote
The Following User Says Thank You to sjgrall For This Useful Post:
heavyduty (07-09-2011)
Reply

Tags
a-40, crossover, t62a-40

Thread Tools
Display Modes

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

Forum Jump


All times are GMT -5. The time now is 09:17 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Template-Modifications by TMS
bazooka.com
SAS, BAZOOKA, BASS TUBES, and LISTEN TO YOUR EARS are registered trademarks of Southern Audio Services, Inc.