Baxandall in Knight PA?

[dmartn149]

I am thinking of building a James/Baxandall tone stack using Adam's Amplifiers layout in my converted Knight PA amp. Adam's Amplifiers: Tone Stacks
I have a couple of questions. Can I just place that whole circuit with the same component values where my one knob tone control is? Do I need to worry about the impedances of the stages before or after? And also, Adam's doesn't include R5 as in Duncan's tone stack calculator. Do I need it, or not?
Thanks

[dmartn149]

Okay, forget Baxandall. I have learned that what I want to do is a "James" tone circuit. Still, what about r5, and can I use this after two stages of 6sc7 and just before the PI. The reason I ask is that on the tone calculator you can change the value of the source resistance, and I have no idea what number to plug in there.