World-Designs-Forum  

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

WAD General For discussions re World Audio Design

Reply
 
Thread Tools Display Modes
  #1  
Old 11th May 2006, 08:37 AM
robaustralia robaustralia is offline
Junior Member
 
Join Date: May 2006
Location: Noosa QLD Australia
Posts: 15
Default Fatter sound from KEL84?

I have a KEL84 that had the R38/220nF mod and it sounded great. I fitted an ALPS Blue and the sound lost it's 'edge' so I removed the mod.
Now the space and transparency is superb but it sounds a bit 'harsh' and 'thin' on some CD's. Live CD's are breathtaking. In fact I have the Herbie Hancock Possibilities CD with a duet and the two voices are totally separated and so focussed you could put a ruler between them.
Is there a fix to 'fatten' the sound without losing the subtle edge or am I just dealing with some bad CD's?
Thanks.
Cheers,
Rob
Reply With Quote
  #2  
Old 11th May 2006, 02:19 PM
pete_b pete_b is offline
Junior Member
 
Join Date: Mar 2006
Posts: 14
Default Re: Fatter sound from KEL84?

Quote:
Originally Posted by robaustralia
I have a KEL84 that had the R38/220nF mod and it sounded great.
Hello Rob,

can you tell me what the R38/220nF is, please?

Pete
Reply With Quote
  #3  
Old 11th May 2006, 02:27 PM
Rob042's Avatar
Rob042 Rob042 is offline
Senior Member
 
Join Date: Jan 2006
Location: Lovely Hampshire
Posts: 251
Default Re: Fatter sound from KEL84?

Pete
you could replace two of your four de-coupling caps with pio's ( coppers).
and then replace the pot with the shunt mod and use say rikens or kiames.
the second idea is cheaper,the first will fill the mid and upper bass while adding a silkiness to the upper frequencies.( all imho).

Rob
Reply With Quote
  #4  
Old 11th May 2006, 08:19 PM
andrew ivimey's Avatar
andrew ivimey andrew ivimey is offline
Senior Member
 
Join Date: Dec 2005
Location: Bedford
Posts: 2,028
Default Re: Fatter sound from KEL84?

G'day Rob in australia,

if you want a decent upgrade to KEL84 (and it is interesting that you found ALps not that good - all I find with Alps os that it guarantees the same resistance on both channels but OTOH, input impedance is a hugely huge subject and worth messing with - if only people would realise - sigh, despairs)

but, I'd search out a quad of reflektor (russian) el84Ms; they are dead cheap if you search on ebay. NOw, maybe Mullard el84s are better - I haven't the foggiest because they are sillly money but these reflektors are the business and very cheap too ( I tried quite a few makes of EL84s, believe me).

I ought to get another KEL84 just to play again - anyone want to sell their's?

OTOH that PCB was a nasty thing to 'modify'.
Reply With Quote
  #5  
Old 11th May 2006, 11:43 PM
robaustralia robaustralia is offline
Junior Member
 
Join Date: May 2006
Location: Noosa QLD Australia
Posts: 15
Default Re: Fatter sound from KEL84?

Hi Pete.
A 220nF/630V poly cap is connected in parallel with R38 in the power supply.
Cheers,
Rob
Reply With Quote
  #6  
Old 11th May 2006, 11:46 PM
robaustralia robaustralia is offline
Junior Member
 
Join Date: May 2006
Location: Noosa QLD Australia
Posts: 15
Default Re: Fatter sound from KEL84?

Thanks all.

We are very deprived over here when it comes to a good supply of quality components, so I'll have to do some hunting around.

Cheers,
Rob
Reply With Quote
  #7  
Old 11th May 2006, 11:52 PM
NickG's Avatar
NickG NickG is offline
Senior Member
 
Join Date: Dec 2005
Location: Halifax, West Yorkshire
Posts: 1,767
Default Re: Fatter sound from KEL84?

Actually, I think you are dealing with bad CD's, and are fixing something that isn't broke. Have you considered vinyl?
__________________
Just about everything I say has been in public use since the 1940's so no one owns the copyright on that.

If by any chance its not prior art, then the copyright is retained by me.
Reply With Quote
  #8  
Old 14th May 2006, 02:31 PM
jimangus's Avatar
jimangus jimangus is offline
Senior Member
 
Join Date: Apr 2006
Location: derby
Posts: 252
Default Re: Fatter sound from KEL84?

Hi rob in oz,
i have just replaced my kel84 pcb and populated it with new components, so i have a few bits of componants i could send to you in oz,
i have 4 x copper jensen p10's
4 elna silmic cathode caps for el84's
2 bg standard for the ecf80 cathods. This should warm your sound up a bit but still give great detail.
I have a spare quad of russian reflectors and a quad of phillips el84's that are very nice.

On the other hand you could try parts connextions, i goT BG N and NX and dynamicaps in my kel, and i have to say it is sounding very good.

That is an unusual comment about the alps pot, i always considered it quite a sweet sounding vol pot, i always used to use them on my tranny amps to sweeten them up a bit.

Send a pm if any of that gear any value to you.

regards
jim
__________________
50,000 housewives ever day pick up a can of beans and say "what an amazing example of syncronisation".
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
KEL84 Sound Richard Howell WD Amplifiers 3 13th September 2006 07:52 PM
What does the Kel84 sound like?? Primalsea WD Amplifiers 22 30th July 2006 06:17 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 05:14 PM.


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