World-Designs-Forum  

Go Back   World-Designs-Forum > World Designs > WD Amplifiers
Register FAQ Members List Calendar Gallery Today's Posts Mark Forums Read

WD Amplifiers For discusson of World Designs Amplifiers

Reply
 
Thread Tools Display Modes
  #1  
Old 11th September 2006, 05:27 PM
Richard Howell
Guest
 
Posts: n/a
Default KEL84 Sound

Hello

I've just built or should I say rebuilt a KEL84. It was the failed kit that was on Ebay a while ago. It sounds very good, especially with some very cheap recent Gale speakers and also via an old pair of Stax headphones.
My main set up includes a pair of Quad ESL63s and a Quad 99 power amp.
It sounds very good with these also (the speakers), maybe more detail than the Quad, but far more bass-light and definitely recessed in the midrange.
I had the wiring problem where the output transformers were wired the wrong way around, so sent positive rather than negative feedback into the amp causing it to oscillate. I had to wire these the opposite way around, would this make any difference to the sound? Or could it be the 63s are too much for the 84s to drive? How would you describe the sound of the KEL84?

I also have a mains transformer that likes to join in with the music... but that's another story.

Richard
Reply With Quote
  #2  
Old 11th September 2006, 07:28 PM
David Mccallum's Avatar
David Mccallum David Mccallum is offline
Senior Member
 
Join Date: May 2006
Location: The wetback
Posts: 322
Default Re: KEL84 Sound

Hi Richard,
in my opinion,the KEL84 has excellant bass for a small valve amp.If it's working correctly that is.Could you check that R8/9 is 22R and not 220R,
bear in mind that the amp will burn in quite a lot from new,bass does improve.
It took around a hundred hours use to fully burn mine in,patience rewarded.
You can upgrade the amp to boost bass weight also,well worth trying a 220Mfd capacitor in place of the one fitted to C3 (100uF).World Designs can supply one for little over a tenner,fit's a treat too.
Look up the thread on the feedback mod,also well worth a try.
You can place rubber grommets under a noisy transformer to good effect.

Hope you get sorted as it's a fine amp indeed,should be capable of driving your ESL63,altho i hav'nt tried them myself.It certainly drives Quad 12l's to ASBO levels though
__________________
Davy
Reply With Quote
  #3  
Old 11th September 2006, 09:29 PM
Richard Howell
Guest
 
Posts: n/a
Default Re: KEL84 Sound

Hello David

Thanks for that, plenty to think about.
I had read about R8/9 and they are 22R rather than 220R.
I'll investigate the feedback mods and then maybe the capacitor.
But as you say I'll let it burn in to see if that alters things.

Regards

Richard
Reply With Quote
  #4  
Old 13th September 2006, 07:52 PM
David Mccallum's Avatar
David Mccallum David Mccallum is offline
Senior Member
 
Join Date: May 2006
Location: The wetback
Posts: 322
Default Re: KEL84 Sound

Give it at least three week's hard use,after that improvement comes slowly up to about 250(aprox hours).Consider it well run in by then,if not satisfied still-try the cap upgrade at least.I dont think your output trannies will have been damaged,but their's people here better qualified than me to answer that one.

Good luck
__________________
Davy
Reply With Quote
Reply


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
What does the Kel84 sound like?? Primalsea WD Amplifiers 22 30th July 2006 06:17 PM
Fatter sound from KEL84? robaustralia WAD General 7 14th May 2006 02:31 PM
kel84 removing volume pot richardcarter WAD General 3 7th May 2006 07:38 PM
WAD KEL34 KIT88 KEL84 KEL80 Known Problems FAQ Team FAQ - Common Problems 0 6th January 2006 09:21 PM


All times are GMT +1. The time now is 03:48 PM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright World Designs