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Translation Russian EL84SE design please?

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Hi,
Just built an EL84 SE with 6AK5 triode connected as input/driver tube. Scorching the net for a similar design I found this Russian gif.
Looks like the Mullard 3W with starved 6AK5?
As I am curious about the text on the gif maybe someone would be willing to translate on headlines? And maybe comment on the design?
I put in a picture of my design as well although she needs her skirt.. :D

Rob
 

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Thanks for quick response!

I don't advice You use 6Ж1П like input tube.
May I ask why? I have it up&running and don't think anything is wrong with it.. The 6AK5 is running at 6mA, Vp 110V and Vg -2V.
Attached the diagram.


You will find it hard to beat the input stage. An EF86 or EF91 (7 pin version) is excellent
What exactly do you mean? Hard to beat the current input stage with 6AK5 or "go convert to EF86/EF91"?

Reason for asking translation is that I am curious about a (maybe) circuit description..
 

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I'd like use another kind schem. with input triod - ECC88, 81, 82, 6SN7, 6SL7, E180F....with better sounding and EL84 in UL mode. I will think about possibility to do schem in Loftin'White mode /without interstage cap/ for more better sounding.
/For exam....I will use +U 450v, cathode res. for EL84 about 2 kohm with current 50 ma,.... input tube ECC88 with U plate about +90 v. Than You can connect plate ECC88 and 1 grid EL84 directly, to avoid interstage cap/.
 
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Hi,
Just built an EL84 SE with 6AK5 triode connected as input/driver tube. Scorching the net for a similar design I found this Russian gif.
Looks like the Mullard 3W with starved 6AK5?
As I am curious about the text on the gif maybe someone would be willing to translate on headlines? And maybe comment on the design?
I put in a picture of my design as well although she needs her skirt.. :D

Rob

Yours looks very nice.. More pix when it is done. I assume PSE output stage?

Despite the superficial resemblance I would not say your design and the vintage Russian design are really all that similar unless you consider two stage designs to be the main criteria.. Current starved first stage with dc coupling as compared to a well biased AC coupled stage, tone controls in feedback loop, etc.

Azazello 450V @ 50mA is going to cook most modern 6BQ5/EL84/7189/6P14P in pretty short order. The 6P14P-EV will survive about 15W combined plate + screen dissipation, but life will be short. The JJ otoh which is also a great tube will go super nova under these conditions.. Ask me how I know.. :hot: :eek:

The Russian design uses 250V and Rob I assume yours is fairly conservative too.
 
I'd like use another kind schem. with input triod - ECC88, 81, 82, 6SN7, 6SL7, E180F....with better sounding
Okay, It seems to me that you are in favor of DC-coupling? My PSU won't allow for more than 320Volts.. So that leaves it out of the possibilities for me..
By the way: Do not underestimate the 6AK5 in triode.. It is linear, easy to incorporate and sounds good in both preamps and as driver in this design.. It has relative high mu but suits the EL84 design. In a preamp I used it with success loading it with a 15K/600ohm output transformer..
Thanks for your suggestions though.. :)

Yours looks very nice.. More pix when it is done. I assume PSE output stage?
The Russian design uses 250V and Rob I assume yours is fairly conservative too.
Thanks! I am tuning it right now. It is not PSE, the second noval tube is a booster diode, an EY80..
It sounds really good, actually that amazed me (to be honest).. A chassis will be made in the upcoming week.
You are right, I have about 300 Volts B+, depends on which diode I use. An EY82 is about 20Volts more efficient..
 
BTW, what is the Lp of the OPT from Musicalpowersupples, please ??

The OPT is a special from Matt, it is an upgrade from his OT10SE. This is what he told me:
I do have a bobbin in stock that would allow about 30% more iron to be used on the same EI-87 lamination. I could wind up a pair of OT10SE "Plus" models and increase the winding interleaving for an improvement in treble over the standard Guitar OT design.

I did a static measurement with my handheld LCR on both 120hz and 1Khz, it was about 18He. I had it made with a 16ohms secondary..
 
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