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 6th May 2020, 05:06 PM
david.rogers david.rogers is offline
Senior Member
 
Join Date: Jan 2006
Location: Oxford and Gubbio, Umbria
Posts: 149
Default WAD v, WD

I'm hoping someone can lighten my darkness. My problem is that some of my equipment and components is at one house, and some at the other. Trying to sort out what I have here (here being near Oxford) I find some components for the WD Pre and a circuit board stamped as WADPre II. I have the circuit diagram for the WD Pre, which is quite different from the WAD, which appears to be a single valve (6922) design. Did WAD morph into WD? If so, what happened to the WAD designs? And can I use the WAD board (without significant deterioration in performance)?

Thanks
David
Reply With Quote
  #2  
Old 6th May 2020, 06:05 PM
Phil Y's Avatar
Phil Y Phil Y is offline
Senior Member
 
Join Date: Jul 2006
Location: Bristol, UK
Posts: 764
Default Re: WAD v, WD

http://www.world-designs.co.uk/forum/showthread.php?t=2
__________________
Commission for Dark Skies (CfDS)
Reply With Quote
  #3  
Old 6th May 2020, 08:58 PM
Richard Richard is offline
Super Moderator
 
Join Date: Dec 2005
Location: Notts
Posts: 4,981
Default Re: WAD v, WD

Hi David, yes the morphing as Phil links to.

Phono2 and 3 were very similar and the first Phono3 used the Phono2.2 pcb.

Pre2 and 3 were very different in circuit, valves and OPTX so need to go together as a set.

The 2 series used the large Cliff umbilical connectors and the 3 used a smaller type who's name escapes me. Bob may know more as I only built the 3 but I think he had both
Reply With Quote
  #4  
Old 6th May 2020, 09:30 PM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 2,049
Default Re: WAD v, WD

David, the II series used Cliff-con connectors and the III series uses Binder 678 series connectors available from Farnell , the two are not interchangeable, the holes in the case are very different in size, in my opinion the Pre II is bloody rubbish compared to the Pre III, although, I ask, do we need any gain at all to drive WAD or WD power amps, for this very reason, WD ( Matthew Snell, very nice chap ) now does a cathode follower Pre. If you need more history of WAD and WD go to the bottom of the page, on the right and click on World- Designs and follow through to history. I hope this helps you, by the way, the Pre II also needs two output transformers, these are very different from the III. Bob
Reply With Quote
  #5  
Old 7th May 2020, 02:28 PM
david.rogers david.rogers is offline
Senior Member
 
Join Date: Jan 2006
Location: Oxford and Gubbio, Umbria
Posts: 149
Default Re: WAD v, WD

Quote:
Originally Posted by bob orbell View Post
An update to Richards part no's 9906150005 Farnell no is now 2949826
and RS Components now stock them 5 pin no's 129-8523
129-8804
129-8753
129-8472
Bob
Thanks for your inputs, guys. I obviously didn't explain myself properly. What I have is the WAD II circuit board, which seems very similar to the layout of the WD3 Pre layout, except it uses a single 6922 valve, with both channels on the same board. I was just wondering if anyone has experience of this board and its performance.

David
Reply With Quote
  #6  
Old 7th May 2020, 03:08 PM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 2,049
Default Re: WAD v, WD

David, if you are asking about the pre II board with the single 6922, my opinion it is rubbish, I had one many years ago, it was very bass light it coursed hum and the gain was massive, 12 dB, the III with two ECC 82 valve's is a different circuit with again different transformers and a choice of 6 or 12 dB gain. Bob
Reply With Quote
  #7  
Old 7th May 2020, 09:19 PM
Richard Richard is offline
Super Moderator
 
Join Date: Dec 2005
Location: Notts
Posts: 4,981
Default Re: WAD v, WD

Hi David, It sounds like you have Pre2. If you PM me your direct email I can send Pre2 and Pre3 build sheets with circuits so you can sort it out.
Reply With Quote
  #8  
Old 8th May 2020, 10:42 AM
Richard Richard is offline
Super Moderator
 
Join Date: Dec 2005
Location: Notts
Posts: 4,981
Default Re: WAD v, WD

Following Bob's comments David if you've not yet built yours, it's fair to say Pre2 was good for many builders and problems really only apply if it has too much gain for your power amp and/or your rack layout means it picks up hum from a nearbye mains TX.

If you've not seen it, Neal Gibbons wrote up a neat FAQ to easily convert it to a cathode follower in the style of the original WAD Line Pre (June 1993 for anyone with the Supplement Disc and Morgan Jones). He details an easy rewire along with removal of the OPTxs which leaves it without gain or hum using the original power supply,

http://www.world-designs.co.uk/forum...ead.php?t=7632

Last edited by Richard; 8th May 2020 at 10:55 AM. Reason: ref Morgan Jones
Reply With Quote
  #9  
Old 8th May 2020, 01:04 PM
david.rogers david.rogers is offline
Senior Member
 
Join Date: Jan 2006
Location: Oxford and Gubbio, Umbria
Posts: 149
Default Re: WAD v, WD

Thanks Richard. I'm

Last edited by Richard; 8th May 2020 at 02:57 PM. Reason: remove email
Reply With Quote
  #10  
Old 8th May 2020, 02:57 PM
Richard Richard is offline
Super Moderator
 
Join Date: Dec 2005
Location: Notts
Posts: 4,981
Default Re: WAD v, WD

Thanks David, I removed your email address to save it from the spam bots.
Reply With Quote
Reply

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 +1. The time now is 01:18 PM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
Copyright World Designs