Amp Furious VaBAnk 70W

[Hennady Kovalsky]

good afternoon,
introduce my amplifier see attachment
Uin max RMS 2.8V
Pmax 70W (4R)
Ku 15dB
K (TND) 0.01%

circuitry in the form of vintage, sounding very good, who are interested in asking questions, who sees errors in topology - write ...
On the forum I happen rarely, I apologize in advance for the slow answers.
with respect
HenK

 

[prasi]

Thanks for posting your work. A fresh and different design. Congratulations!
regards
Prasi

 

[Hennady Kovalsky]

Thank you.
The scheme is sufficiently technological, it works immediately after switching on.

 

[__BriKs__]

It looks like you sucessfull avoid ac input coupling cap, very interesting!
I'm trying to supress input cap in an amp design (single supply, input diff pair polarized about vcc/2) with jfet also, then your design is very interesting for me.

Regards,

 

[thimios]

Thanks for posting your work. A fresh and different design. Congratulations!
regards
Prasi

Ha Prasi ...new troubles on the road!

 

[prasi]

, want to build this one as well?

 

[Hennady Kovalsky]

I will add frequency response and the spectrum of distortions on the first Watt

 

[prasi]

Hello Hennady,
Could you kindly take a look at my drawing of your schematic and advise about
1. Grounding scheme
2. Resistor wattages of R9/R11. Except specifically mentioned wattages, I have used 0.5W package for resistors (10mm pitch).

regards
Prasi

 

[Hennady Kovalsky]

Hello Hennady,
Could you kindly take a look at my drawing of your schematic and advise about

Hello Prasi.
Wow, good work. I have some tips:
1) the arrangement of the elements D2,R5,J4,Q6,J1 end D1,R4,J2,Q5,J3,R16 according must be the same on the Plate
2) Cap C1,C2 should be near
3) with the help of R5 half of the power is adjusted, it can be either a resistance of 91Ω or 110Ω ohms so it is desirable to make it out of two for example 75Ω and 25Ω ohms, for tuning or 75ohm constant and 50 ohm treemer.

1. Grounding scheme

See attachment, I corrected.

2. Resistor wattages of R9/R11. Except specifically mentioned wattages, I have used 0.5W package for resistors (10mm pitch).
regards
Prasi

ok, 0.5W normaly.
these resistors determine the initial current of the output transistors, the higher they are the higher the current the higher.

see attachment:

 

[Hennady Kovalsky]

D1 end D2 need to use Phillips 1.5W (BZV85C15)

 

[Hennady Kovalsky]

the scheme received a slight change.
The variant of this scheme was called "dickens"
in the attachment scheme and photo-view board