Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  
previous: Morris I have some questions about cathode... -- 5/2/2000 5:42 PM View Thread

Re: Cathode Follower Questions

5/2/2000 7:42 PM
Re: Cathode Follower Questions
morris, let me see if i read you correctly...  
plate loaded stage  
direct coupled from plate to grid of  
cathode follower with resistance in cathode circuit  
AC coupled (through cap) from cathode to one side of center tapped choke  
center tap to ground  
floating ends to output grids  
in terms of which value of cathode resistor, just measure your voltage on the plate loaded stage's grid, which will be the approximate voltage on the cathode of the cathode follower. you can size the cathode resistance of the cathode follower using R=V/I. i'd say pull a couple of mils through it--that's really all you need. the gain through the CF won't change much with varying plate currents. because of the 100% degeneration going on, the CF's don't need very much current at all to be linear as all hell.  
i like the inductive phase inversion/grid impedance. the outputs will be VERY stable with such a low DCR path to ground... not much chance of runaway here!  

Morris I believe you have it down. I'm tr... -- 5/2/2000 8:12 PM