PI ?

[shooter]

Trying to figure out the results of the 100K in the thumbnail below.
My guess is  VERY? Unbalanced signals as PA drive.
thanks

[PRR]

> My guess is  VERY? Unbalanced signals as PA drive.

Why??

The naked grid is >100MEG. Another 100K in front is not a big difference.

There's some Miller effect. Still flat to 16KHz. And the whole power section appears to have NFB which may pull it out a little more.

Williamsons often have 47K there.

[shooter]

Thank you!, As I was trying to sleep my brain came up with about that, 100k/1M isn't that much.  This is my 1st PI of this type.  I like trannies, less work

[HotBluePlates]

Trying to figure out the results of the 100K in the thumbnail below. ...

It is being used to smooth the distortion of the phase inverter during clipping.  See "The input coupling capacitors" section here.