Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Tubes / Valves All about our sweet vacuum tubes :) Threads about Musical Instrument Amps of all kinds should be in the Instruments & Amps forum

How to gap output transformers?
How to gap output transformers?
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
Thread Tools Search this Thread
Old 5th May 2011, 12:46 PM   #1
quikie22 is offline quikie22  Malaysia
diyAudio Member
Join Date: Sep 2009
Default How to gap output transformers?

I have 2 cheapie OPTs. They are non-gapped and thus prone to saturation st higher powers. I plan to take apart the laminations and gap it. Anyway to calculate the ideal gap distance? Any particular material I should use? A friend has suggested using simple 70gsm paper. Any thoughts?
  Reply With Quote
Old 5th May 2011, 02:36 PM   #2
Alastair E is offline Alastair E  Wales
diyAudio Member
Alastair E's Avatar
Join Date: Feb 2004
Location: South Wales
Assuming SE trans......

No point in gapping p-p to my knowledge, you'll just lose inductance when you do...

Even a cheapo SE trans will be gapped--even those in old radios and TV sets Ive seen were gapped...

Gap on average is 0.2mm--Good starting point, Measure, tweak and measure again.....

So--That mans you need a 0.1mm thick material. (mag gap is double the thickness of material--crosses gap twice....)
  Reply With Quote
Old 5th May 2011, 06:08 PM   #3
quikie22 is offline quikie22  Malaysia
diyAudio Member
Join Date: Sep 2009
you are right.. SE trans

these are real cheapies around 4GBP ea. E-I core with alternating E-I laminations. NO GAP for sure. maybe around 5-10W max.

While waiting for answer decided to try it out by unlaminating the core and rearranging the E and the I. Tried a with 80gsm A4 paper and also dot matrix printer paper (thin type, feels thinner than 70gsm paper) to gap the Es and the Is.

Findings are 80gsm paper is too thick, loss of bass. changed to the thinner paper, sounds better than ungapped, but am sure things can be improved.

Any other suggestions of materials I can try? Does it make a difference wht material is used?
  Reply With Quote


How to gap output transformers?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Crazy idea: Output tranny with constant magnetic gap? Wavebourn Tubes / Valves 11 17th April 2010 09:24 AM
Difference between SE output transformer and push-pull output transformers hilbert_mostert Tubes / Valves 12 8th March 2009 05:10 PM
Help identifying a pair of output transformers and power transformers mjk130 Parts 3 30th January 2009 10:44 AM
Output Transformer Air Gap sousmielie Tubes / Valves 3 25th July 2008 11:28 AM
What is the science behind the gap? Paul W Planars & Exotics 2 19th August 2006 04:41 AM

New To Site? Need Help?

All times are GMT. The time now is 12:52 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio