please help ! 5687 cd player buffer

[costa23]

Hi Guys.
I'm trying to replace my cd player op amp buffer stage, with 5687 tube buffer stage.
I think the cathode follower topology is good for buffer.
I wanna try the simple Cathode follower with. 5687 tube.

Please help me, which operating point should I use ?
How about the B+, Vp, and Rk ?

Thanks for all ur kindness.

 

[tubesteve]

5687

5687 is a nice tube. so, it all depends on the voltage you have avalible and your max. audio input voltage. it can work nicely with already 100V DC at around 5 mA plate current and ~50V DC on the plate. but other possibilties are given. RK then would be ~ 390 Ohm and Rplate ~ 10KOhm. just take the graph for making the loadline for your voltage not exceeding the max plate ratings.

 

[costa23]

Thanks for ur advise n explanation.
What topology is ur advise ?
I think that is anode follower ? Correct me if I'm wrong.

 

[costa23]

I plant to build the simple cathode follower with :
Vp = 150 Volt
Rk = 7.5 K. => thus the current is 10 mA.
Is this right ? Please tell me. I'm still learning.

Thanks