Author Topic: U52 Rectifier Tubes  (Read 7901 times)

Offline Peter A

  • Newbie
  • *
  • Posts: 45
  • Liked: 0
U52 Rectifier Tubes
« on: February 08, 2013, 08:34:56 AM »
I have just purchased at KB/Z manufactured GEC U52 tube.  Steve can you please response and enlighten us about this wonderful tube.  What is your experience with this tube and your recommendations.

Thanks

Peter

Offline ozmillsy

  • Hero Member
  • *****
  • Posts: 2164
  • Liked: 245
Re: U52 Rectifier Tubes
« Reply #1 on: February 08, 2013, 09:16:47 AM »
That tube is a favourite of Williams.   I think he has bought all remaining KBZ's that Steven had.    I have 1, I find it very alive, compared to my other rectifiers.   

William, what do you find are the strengths of this tube?
It's all about the music,, not the equipment.

Offline Jehuty

  • Hero Member
  • *****
  • Posts: 1385
  • Liked: 110
Re: U52 Rectifier Tubes
« Reply #2 on: February 08, 2013, 11:41:30 AM »
That tube is a favourite of Williams.   I think he has bought all remaining KBZ's that Steven had.    I have 1, I find it very alive, compared to my other rectifiers.    

William, what do you find are the strengths of this tube?

Hi oz, yes that's correct, I bought Steve's last three KB/Z, it just works so well in my system where initially I found my system to be a bit thick and slow. The KB/Z adds that bit of clarity and speed my system needed, I tried three different U52s and my system lost that aliveness you mentioned. Steve once said the KB/Z was more, for the lack of better word, analytical. Sure the KB/Z has less liquidity and weight but for me, it simply has that PRAT which makes my foot tapping to the music  ;D
Not all that matters can be measured, not all that can be measured matters.

Offline Peter A

  • Newbie
  • *
  • Posts: 45
  • Liked: 0
Re: U52 Rectifier Tubes
« Reply #3 on: February 08, 2013, 04:51:54 PM »
William, thanks for your reply. 

To everyone, how about the other brown base U52 with different manufacturing codes on the glass?   What are your thoughts.

Steve said the brown base U52 are much better than the black base.  What are your thoghts on this.

Offline stevenvalve

  • Administrator
  • Hero Member
  • *****
  • Posts: 1490
  • Liked: 259
Re: U52 Rectifier Tubes
« Reply #4 on: February 09, 2013, 12:09:09 AM »
William, thanks for your reply.  

To everyone, how about the other brown base U52 with different manufacturing codes on the glass?   What are your thoughts.

Steve said the brown base U52 are much better than the black base.  What are your thoghts on this.
Peter the problem in putting info about these U52 - 5U4G tubes on this forum is to make them even harder and costlier to get, publicity is bad in this instance. first of all they are all made in England and have a house sound . That said, the curved brown base U52 is an audio based tube. I believe the curved black base is an industrial tube, and that is reflected in the black bases sound, darker rougher courser. The brown is much more natural smooth relaxed open without the darkness, as for the codes the GEC - KBZ factory made coded brown base, is faster clearer cleaner but not as much body and liquidity as the slower fatter rounder harmonically richer models. you need to know the codes to get the right ones and that is a problem to print here. The Osrams are a very rich full fat liquid tube and in the right system all of these tubes can and are great. In my system i use the highest grade Genalex gold lion curved brown base U52 only made for the USA market in 1960. They have it all and are better than the Western Electric 274B and 274A tubes .
« Last Edit: February 09, 2013, 12:21:27 AM by stevenvalve »

Offline Peter A

  • Newbie
  • *
  • Posts: 45
  • Liked: 0
Re: U52 Rectifier Tubes
« Reply #5 on: February 09, 2013, 01:12:58 PM »
Steve, thanks for your reply.  Have you managed to get some STC 4212E or WE 212E tubes for an ultimate amp.  All the best

Peter

Offline Erik van Voorst

  • Sr. Member
  • ****
  • Posts: 272
  • Liked: 2
Re: U52 Rectifier Tubes
« Reply #6 on: February 19, 2013, 10:37:12 PM »


In a shoot out my U52 tube was clearly the winner over the G37 Mullard and a G37 Japanese
It was expensive (300 dollars) but I think worth it because the diffrence was substantial.

Offline stevenvalve

  • Administrator
  • Hero Member
  • *****
  • Posts: 1490
  • Liked: 259
Re: U52 Rectifier Tubes
« Reply #7 on: February 20, 2013, 01:58:16 AM »
Eric, I think they are the best rectifier on the planet, but they can and do sound very differant to each other. The year and factory is most important. How do you know the best for you. By knowing what you need (soundwise) in your system and then know which one to get (via the codes). PS Eric the brown base is much better.

Offline Erik van Voorst

  • Sr. Member
  • ****
  • Posts: 272
  • Liked: 2
Re: U52 Rectifier Tubes
« Reply #8 on: February 20, 2013, 04:15:42 AM »
I need a spare one anyway so I am open to beautiful suggestions (link)  ;D

Offline Jehuty

  • Hero Member
  • *****
  • Posts: 1385
  • Liked: 110
Not all that matters can be measured, not all that can be measured matters.

Offline stevenvalve

  • Administrator
  • Hero Member
  • *****
  • Posts: 1490
  • Liked: 259

Offline Jehuty

  • Hero Member
  • *****
  • Posts: 1385
  • Liked: 110
Re: U52 Rectifier Tubes
« Reply #11 on: February 20, 2013, 03:50:00 PM »
Measured new  ;D

Edit: And leave the cheap ones for me  :P
« Last Edit: February 20, 2013, 03:51:55 PM by Jehuty »
Not all that matters can be measured, not all that can be measured matters.

Offline Jehuty

  • Hero Member
  • *****
  • Posts: 1385
  • Liked: 110
Re: U52 Rectifier Tubes
« Reply #12 on: February 20, 2013, 03:55:33 PM »
And if you think that's expensive, look at this one: http://www.ebay.com.au/itm/221189874228

Well at least it's new...
Not all that matters can be measured, not all that can be measured matters.

Offline kajak12

  • Hero Member
  • *****
  • Posts: 2445
  • Liked: 67
    • http://killerdac.com/forum/index.php
Re: U52 Rectifier Tubes
« Reply #13 on: February 20, 2013, 05:04:01 PM »
And if you think that's expensive, look at this one: http://www.ebay.com.au/itm/221189874228

Well at least it's new...
I think this thread should be deleted due to the price increase of u52
still discovering the link between electronics and audio reproduction.so much to learn and so little time

Offline Jehuty

  • Hero Member
  • *****
  • Posts: 1385
  • Liked: 110
Re: U52 Rectifier Tubes
« Reply #14 on: February 24, 2013, 04:00:30 AM »
A pair of U52 Osram Z coded 1950's vintage tubes black plate went for....$650 plus shipping http://www.ebay.com.au/itm/290864658565

Time to close the thread.
Not all that matters can be measured, not all that can be measured matters.

Offline ozmillsy

  • Hero Member
  • *****
  • Posts: 2164
  • Liked: 245
Re: U52 Rectifier Tubes
« Reply #15 on: February 24, 2013, 08:30:36 AM »
Nice tubes,  not perfect,  the writing was worn.   Could barely see the Z's. 

If it was $650ea, I'd be worried.

It's all about the music,, not the equipment.

Offline Erik van Voorst

  • Sr. Member
  • ****
  • Posts: 272
  • Liked: 2
Re: U52 Rectifier Tubes
« Reply #16 on: February 26, 2013, 07:31:57 AM »
I am seriously on the lookout for a spare U52....maybe someone could give me via PM a bit guidance/link since I am new with this tube....  ;)


Offline Erik van Voorst

  • Sr. Member
  • ****
  • Posts: 272
  • Liked: 2
Re: U52 Rectifier Tubes
« Reply #18 on: February 28, 2013, 04:23:33 AM »
I will have a look....thanks  8)

Offline Jehuty

  • Hero Member
  • *****
  • Posts: 1385
  • Liked: 110
Not all that matters can be measured, not all that can be measured matters.