ECL82 PP "reference" amp

[Tyimo]

Hi!

I would like to buid a simple and good PP amp for reference and to listen and demonstrate the sound of the PP tube amps.

I found a couple (or 3-4-5 ) of interesting circuits, but I don't know which one is the best....

Here are the competitors:

- Mullard 7W classic amp
- Audio Innovation 300 Mk2
- Svetlana 6BM8 (from Sansui)
- No name (suggested by Sjef)
- Rainer zur Linde amp

Has somebody experiences with these amps?
Which one can operated in Ultra Linear mode and is it worth it?
For the output transformator I thought on the Hammond 1620.

Greets:

Tyimo

Here is the Mullard:

[Tyimo]

Here is the Audio Innovation300Mk2:

[Tyimo]

Here is the Svetlana 6BM8-("Sansui"):

[Tyimo]

Here is the No name (by Sjef):

[Tyimo]

Here is the Rainer zur Linde amp:

[planet10]

None of the above (really onlt variations on 2 topologies).

Yves & Gingertube worked out an ECL86 PP with a Long Tail Pair loaded by a CCS and RH style (plate-to-plate) feedback.

Hey Planet_10 (and others)

dave

[Shoog]

I'm having really good result with the attached schematic of my own design. I'm using it as a headphone amp, but by choosing the correct output transformer you should hget good performance with speakers.
Fully differential from input to output. No cathode bypass on the input LTP. Differential output stage with self balancing bias circuit.

Based on Gary Pimms Tabor circuit. I love listening to it.

PS. R11 should be 800R.

Shoog

[Tubes4e4]

Hi Tyimo,

I would suggest to add the German Klein+Hummel Telewatt VS55 circuit to your list. Klein+Hummel (still) is a producer of broadcasting & studio gear and back in the old times also had a line of amps for demanding private customers.

I once had such a VS55 on my bench for restauration, which thaugth me a *lot* on professional circuit design; it has some very interesting aspects almost nobody cares about nowadays for some unknown reasons.

But you can find pictures, description and schematic here at this link.

Sound is outstanding for an amp using "sh*tty TV tubes" like ECL82/6BM8, I can asure you.

A problem for your project will be that the Hammond OPTs you have in mind quite likely don´t come anywhere close to the quality of the OPTs like being used in a K+H VS55 amp or comparable gear. In this regard, you should use really good OPTs in the first place when heading for a "reference" class project

Regards,

Tom

[Tyimo]

Thanks Dave and Soog!

None of the above (really onlt variations on 2 topologies).

Dave, sorry, but what do you mean?? Did you answer for this question: "Has somebody experiences with these amps?" or for this: "Which one can operated in Ultra Linear mode and is it worth it?"

Do you suggest this:

Greets:

Tyimo

[planet10]

Originally posted by Tyimo
Do you suggest this:

yes.

I have a donor downstairs & that is what i'm going to build. (but in pentode mode -- i don't have UL OPTs

dave