Tube Phono Pre of RJM

[ebijma]

RJM has this Tube phono pre on his website.

http://www.geocities.com/rjm003.geo/rjmaudio/diy_pho1.html

It's very nice for a tube starter like me.
Do some of you have a idea on how to improve this design?
I have already put RJM updates on the circuit in the drawing you can see underneath.

 

[analog_sa]

Do some of you have a idea on how to improve this design?

I don't get it. Why pick the worst possible tube design and then improve it? With about the same effort you'd build something decent like an EAR834.

 

[ebijma]

I don't get it. Why pick the worst possible tube design and then improve it? With about the same effort you'd build something decent like an EAR834.

Because im a tube starter.
In faqt my first project with tubes.
So...........

 

[Frank Berry]

Add a cathode follower output stage to lower the output impedance.

 

[ebijma]

Add a cathode follower output stage to lower the output impedance.

What do you think the output impedance is of this circuit?
(without the cathode follower idea)

 

[hifidaddy]

I don't get it. Why pick the worst possible tube design and then improve it? With about the same effort you'd build something decent like an EAR834.

indeed, without the tube follower, this looks like a simplified version of the EAR 834. Second tube works like a current to voltage converter and delivers virtual ground (constant voltage) for first tube's anode.

Anyway, did anybody compare RJM and EAR 834 ?

regards,
Hartmut