• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Studer 52

Franz Gysi

Member
2007-10-28 9:29 am
Hi

I want to show you a circuit, I found last week in the Studer archive:

The Studer 52

[IMGDEAD]http://image.n0t.de/page.php?type=gif&f=72c035f4f925081e67112456a0da5563[/IMGDEAD]

Isn't this a very nice circuit?

Carefully selected tubes, DC coupled phase inverter, cathode feedback output transformer.

Not one part to much, fine engineering work.

A little Swiss Quad II?

I don't know, how many of them where produced. I have never seen one of them.

But it could be a very nice project to rebuild, isn't it?

Kind regards
Franz
 

tubewade

Member
2007-06-03 8:54 pm
Yes, it is a very nice circuit. I like the Mullard front end and the cathode feedback configuration. I also like 6BQ5/EL84s very much. I have an amplifier that is very similar to this one but does not use cathode feedback.

Thank you for sharing this schematic with us.

Wade
 

Franz Gysi

Member
2007-10-28 9:29 am
Hi

I can share more info with you: the production datasheet from the output transformer (sorry, written in German):

[IMGDEAD]http://image.n0t.de/f-3c3faa72bbec522ea4215af3bc5c43f5.gif[/IMGDEAD]

[IMGDEAD]http://image.n0t.de/f-1b31bf7aacfc63e201ded0bbb44cea82.gif[/IMGDEAD]

BTW:

I plan to rebuild this promising circuit. I ordered output transformers specially for this project from www.roehrentechnik.de, from Gerd Reinhoefer. He will produce them following the datasheet, but using a double chamber in M102 format and todays iron quality. It will be a very well sized tranny for this amp. The price will be the same like the production trannies, he is offering!

Should you want the original circuit and the tranny datasheet in PDF, just drop me a mail under firstname dot name at studer dot ch

Kind regards
Franz
 

Franz Gysi

Member
2007-10-28 9:29 am
Yes! And it was me (proud) having discovered both circuits in the Studer archive while I was a Studer employee.

For the EL34 version I could not find the datasheet of the output transformer but a Lundahl LL1620CFB should do the job.

For the EL84 version there is a fine offering available here Gegentakt

Look for the 53.1S52 type (do you recognize the S52 in the product number?)

Happy ears!
Franz