World-Designs-Forum  

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

Amplifiers Your DIY amplifier designs

Reply
 
Thread Tools Display Modes
  #1  
Old 26th July 2022, 10:16 PM
Desmodromic's Avatar
Desmodromic Desmodromic is offline
Member
 
Join Date: Jun 2007
Location: Hertfordshire
Posts: 69
Default Elekit TU-8900 2A3/300B kit amp

Anyone else built one of these? I got mine from Nick @ HiFi Collective, and it's just wonderful. I'm using 2A3 valves at the moment, and I don't really feel the need to try out the 300Bs. These are delivering everything that I've ever read about SET valve amplifiers. I never saw or heard the WAD 2A3 amp, but if it's anything like the Elekit then it must have been quite something.
I went for the Lundahl output transformer option. https://www.hificollective.co.uk/kit...-tu-8900r.html
Reply With Quote
  #2  
Old 27th July 2022, 10:21 AM
Mark Mark is offline
Senior Member
 
Join Date: Feb 2007
Location: London
Posts: 153
Default Re: Elekit TU-8900 2A3/300B kit amp

The TU8900 rated power output with 2A3 valves is only 3.5W, so I would be interested to hear what speakers you use.
Reply With Quote
  #3  
Old 27th July 2022, 11:11 AM
Desmodromic's Avatar
Desmodromic Desmodromic is offline
Member
 
Join Date: Jun 2007
Location: Hertfordshire
Posts: 69
Default Re: Elekit TU-8900 2A3/300B kit amp

Hi Mark,

I confess I was a bit concerned, having read all the talk of needing super sensitive loudspeakers for a 2A3 valve amp, but I have been very pleasantly surprised.

I use a pair of rather elderly B&W P6 floor standing loudspeakers. I believe that they have a sensitivity of c.89 or 90dB. They go plenty loud for me. I don't usually play my music at neighbour annoying levels, but I think at full volume they'd notice!

My last setup involved either a pair of Quad 306s bi-amping the same speakers, or a single Quad 520F. I really don't feel any lack of oomph with the Elekit, and the extra sparkle, ambiance, and detail from the valves has got me going through all my old WAD kit and looking to dust them off. First stop was my KECL 82 with an output of 8 or 9W. It too drives the speakers perfectly well, though I can't see it replacing the Elekit in my main system any time soon.

Hope that helps.
Reply With Quote
  #4  
Old 27th July 2022, 12:19 PM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 2,734
Default Re: Elekit TU-8900 2A3/300B kit amp

Interesting, I have never heard of a WAD KECL82, please enlighten me. Bob
Reply With Quote
  #5  
Old 27th July 2022, 12:53 PM
Desmodromic's Avatar
Desmodromic Desmodromic is offline
Member
 
Join Date: Jun 2007
Location: Hertfordshire
Posts: 69
Default Re: Elekit TU-8900 2A3/300B kit amp

KECL 82

The original announcement was in an article called 'Bargain Bulbs' in the HFW supplement December 2002. Page 98 - 101.

To quote Nick Lucas "The KECL 82 was created from a brief that demanded simplicity, ease of build, and a super low cost."

The amp only uses 4 x ECL82 valves in a push-pull arrangement.

It was a single source power amplifier with volume control. Exactly like the Elekit TU-8900

It was designed by "Andy Grove", and Simon Pope gave it a glowing review at the time. "The KECL 82 is a bit of a steal at the price. Its sound quality at least equals any £600 amplifier you can name on the market, plus it has all the sonic virtues that come with a pure valve amp design. ... the valves inside the amp, whilst small, are quite robust sounding, with commendable clout and bass depth for a humble budget 9W valve amp."

At the time, December 2002, the kit retailed at £195 incl. VAT and carriage.

I bought mine second hand quite a few years ago, and I used it in my second system for a while till one channel went down. I did the usual and put it aside to be looked at one day, and substituted in a Quad 303. Only recently with my newly revived interest in valves, have I resurrected it, and it's working very nicely. (The problem was a failed capacitor). Like all WAD amps it responds well to the usual tweeks/upgrades.

My next task is to resurrect a KEL 34 that I acquired part built a few years ago. I think it is a candidate for building as a single source power amp with volume control. Should be fun!

Last edited by Desmodromic; 27th July 2022 at 02:51 PM.
Reply With Quote
  #6  
Old 27th July 2022, 03:44 PM
Greg.'s Avatar
Greg. Greg. is offline
WD Archivist
 
Join Date: Dec 2005
Location: Bristol, UK
Posts: 3,582
Default Re: Elekit TU-8900 2A3/300B kit amp

Desmo, if by chance you have the build instructions for the KECL82, I’d appreciate a copy for the WAD/WD archive. If you can help, I’ll PM you my contact details. Thanks, Greg.
Reply With Quote
  #7  
Old 27th July 2022, 04:00 PM
Desmodromic's Avatar
Desmodromic Desmodromic is offline
Member
 
Join Date: Jun 2007
Location: Hertfordshire
Posts: 69
Default Re: Elekit TU-8900 2A3/300B kit amp

No worries Greg,

Yes I do have a scan of the KECL82 Assembly Instructions etc. I'll be happy to send you a copy for the archives. I don't think that WAD sold all that many KECL82s.
Reply With Quote
  #8  
Old 27th July 2022, 04:06 PM
Greg.'s Avatar
Greg. Greg. is offline
WD Archivist
 
Join Date: Dec 2005
Location: Bristol, UK
Posts: 3,582
Default Re: Elekit TU-8900 2A3/300B kit amp

Excellent! Thank you. I’ll PM you my email address.
Reply With Quote
  #9  
Old 28th July 2022, 08:25 AM
bob orbell bob orbell is offline
Senior Member
 
Join Date: Nov 2009
Location: kettering northants.
Posts: 2,734
Default Re: Elekit TU-8900 2A3/300B kit amp

Thank you Desmo. I think you will like the KEL34, very under rated valve. Bob
Reply With Quote
  #10  
Old 28th July 2022, 10:02 AM
Desmodromic's Avatar
Desmodromic Desmodromic is offline
Member
 
Join Date: Jun 2007
Location: Hertfordshire
Posts: 69
Default Re: Elekit TU-8900 2A3/300B kit amp

Quote:
Originally Posted by bob orbell View Post
Thank you Desmo. I think you will like the KEL34, very under rated valve. Bob
Thanks Bob, the original Mk1 KEL34s came with Ei brand 6CA7 valves, so I'm looking forward to hearing them, and seeing if there's any difference to an EL34.

At the time, Nick Lucas from WAD said that they selected the 6CA7 over the EL34 for their sound quality and robustness.

"The sound quality of the 6CA7 is impressive. It's slightly different from the characteristic EL34 sound, displaying smoother treble, more open mid-range and tauter deeper bass."

All the other valves WAD supplied with the Mk1 kit were also from Ei, and the part built kit that I acquired, came with a full set of unused original valves. Let's see if they survived nearly 20 years in someones garage...
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


All times are GMT +1. The time now is 09:44 PM.


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