A Audio and hi-fi forum. AudioBanter.com

Go Back   Home » AudioBanter.com forum » rec.audio » Vacuum Tubes
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Copper Band in a Cross-Over Choke??



 
 
Thread Tools Display Modes
  #1  
Old December 8th 15, 09:31 AM
John L Stewart John L Stewart is offline
Senior Member
 
First recorded activity by AudioBanter: Jan 2011
Location: Toronto
Posts: 301
Smile Copper Band in a Cross-Over Choke??

What measurable benefit might this copper band have? There is what looks like a connexion to go to ground.

Audiophools bad dream or something new?? Anybody got any ideas??

Cheers to all, John L Stewart
Attached Images
 
Ads
  #2  
Old December 10th 15, 12:52 PM posted to rec.audio.tubes
Peter Wieck
external usenet poster
 
Posts: 2,418
Default Copper Band in a Cross-Over Choke??

David Hafler put copper bands on most of his solid state amp transformers. HK did it for some of theirs. Apparently (offered without factual reference) it is a combination shield and hum - audible - damper. It is called a "flux damper", and may be grounded to the secondary, or not.

Hope that helps.

Peter Wieck
Melrose Park, PA
  #3  
Old December 14th 15, 01:57 PM
John L Stewart John L Stewart is offline
Senior Member
 
First recorded activity by AudioBanter: Jan 2011
Location: Toronto
Posts: 301
Smile

Quote:
Originally Posted by Peter Wieck View Post
David Hafler put copper bands on most of his solid state amp transformers. HK did it for some of theirs. Apparently (offered without factual reference) it is a combination shield and hum - audible - damper. It is called a "flux damper", and may be grounded to the secondary, or not.

Hope that helps.

Peter Wieck
Melrose Park, PA
Thanx for your response Peter but it is an air cored cross over choke, not a transformer. And the copper band is a right angles to the winding so that coupling would be at a minimum.

We do see Faraday shields often used in PTs to minimize coupling both forward & reverse to the line. I once used a simple piece of steel sheet between at PT & OPT to reduce the incidental coupled hum component. Don't have any numbers on the hum reduction but the audible difference was significant.

Sofar that copper band is a mystery. I guess someone has a reason, we will see!!

Cheers to all, John L Stewart
  #4  
Old December 15th 15, 05:07 PM posted to rec.audio.tubes
Peter Wieck
external usenet poster
 
Posts: 2,418
Default Copper Band in a Cross-Over Choke??

John:

Same issue, only more so. A choke, typically, a hot source for stray magnetic fields and an air choke would generate those fields in a fairly predictable manner such that a "flux damper" of a specific configuration might be just the ticket. Tha bean counters have me amplifier real estate too expensive to allow extra space for isolation. This may be an accommodation.

Peter Wieck
Melrose Park, PA
  #5  
Old December 18th 15, 03:42 PM posted to rec.audio.tubes
Peter Wieck
external usenet poster
 
Posts: 2,418
Default Copper Band in a Cross-Over Choke??

Perhaps a clarification might be in order. A *speaker* using conventional voice coil and magnet drivers hates stray fields. So, even a choke may need to be damped.

Peter Wieck
Melrose Park, PA
 




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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
WTB: UTC Choke Jon Yaeger Vacuum Tubes 0 February 10th 08 03:44 PM
FA: Precision Power PPI equalizers - 30 band trunk mount & 5 band in-dash packrat014 Car Audio 0 May 29th 06 07:43 PM
Common mode choke in choke input power filter: some conclusions Andre Jute Vacuum Tubes 8 April 20th 06 08:26 PM
flux band around filter choke? jeff kapp Vacuum Tubes 4 November 26th 05 06:05 PM
(OT) Why can't churches just call a band, a band? Leon Trotsky Pro Audio 223 June 24th 04 08:33 PM


All times are GMT +1. The time now is 06:19 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.
Copyright 2004-2022 AudioBanter.com.
The comments are property of their posters.