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Someone help: SE shematic with GK71?

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Thank You for Your reply...
In the beginning when I wanted to make some SE "monster" I go gor GM70 choice, but there is so difficult getting two of GM70, and then i go to second choice - GK71, that's because i already have these tubes. But I don't think that GK71 is analog to GM70... even in triode use... :(
The polish link I know from before, but the other is new to me, but thank You for the links ...
The question is remain the same- the sheme with GK71 in SE
maybe with 6c33c or gu50 - driver... I don't know yet...
any suggestions are necessary and welcome! :angel: :)

May be you can use ECL86 to drive GK71. Here is the shematic.


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6H7C + Gm-70

I bought 17 ea. GM-70 tubes for my projects in Russia and planning to make se amp using 6H7C triode tube as driver. I was talked by Russian old guys that, this driver tube will give me good result with GM-70. I want to use 800-900v DC. I will use silicone diode rectifiers. Do you have any shematic for this?


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hm... i have to think about this...

I think that 6n8s is better than 6n7s in this case because i may use only one tube for two gk71... and i've heard from some diyers that 6n8s is more musical tube than 6n7s
In the other case look at attachment for interesting sheme with GM70 from A.Manakova - one of the best RU diyers :)
Best Reggards

p.s. and what about output transformers?
i've heard for something Turkish firm that make this kind of transformers?


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How much gain do you want?

I wasn't able to find the datasheet of the GK71. But anyhow, if is similar to the GM70, you could probably use the 417A or the 6C45PE as a single driver tube.

That way, you could keep a two stage topology and as both driver tubes will give a relatively low output impedance stage, you probably won't need an interstage trans.


I projected some small amp ;) Look on this picture and say what do you think about it.
I going to make in this year:) .
Other version of this project:
V1,V2 without changes. I would like cut V3 because it is unnecessary when V4 (GK71) working in A2. I don't like A2:smash: Only A1.

PS. Sorry but my English language is not very good
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