PSRR of CF w/ CCS Sink

[regal]

Does the PSRR of a Cathode Follower get better using a CCS sink on the cathode?

 

[SY]

The CCS isn't a miracle- it just means that the load being driven dominates the cathode impedance. So once the CF is actually asked to drive anything, the CCS is pretty much out of the picture except as a means of biasing.

edit: BTW, there was an equivalent circuit of a plate driven tube posted a couple days ago. This is perfect for calculating PSR.

 

[StoneT]

Wierd, I just posted pretty much the same question but more like 'why doesn't it get better?'
To my mind it should but I must be missing something.

edit: oops, in my example the output is between cathode and +HT. For normal operation I would expect it to get worse.

 

[oldeurope]

#1 #3

Originally #1 posted by regal
Does the PSRR of a Cathode Follower get better using a CCS sink on the cathode?

Hello regal,

no of course not, but Aikido does.

Originally #3 posted by StoneT
Wierd, I just posted pretty much the same question but more like 'why doesn't it get better?'
...

Hello StoneT,
for the supply rail voltage ripples the follower acts as a
triode in the transformer mode. link

Kind regards,
Darius

 

[regal]

Now I am going out there but would PSSR be better with a
CCS GC -> CF CCS Sink vs. a SRPP?

Just trying to decide if I should revamp my SRPP DAC stage, I hate the fact that its lowest distortion is into a 6K load. Getting glare in the upper mids. No room for an Aikido or new PS.

 

[oldeurope]

Now I am going out there but would PSSR be better with a
CCS GC -> CF CCS Sink vs. a SRPP?

...

SIDUT
KRD

 

[StoneT]

Regal: GC - gainclone? Huh?


oldeurope: Very interesting page your explanation of 'transformer' action is about what I'd expect, which should be good for an output referenced to the +HT rail. but my simulation (see 'harmonic parrot food' thread) shows a poor performance.

 

[regal]

No, grounded Cathode (CCS plate) into the Cathode Follower (CCS sink).