baxandall tone stack questions

[caress]

so i don't know too much about baxandalls - i've known more-or-less what they are, but finally just started getting interested in them recently.
are the treble and bass controls dependent on each other?
is it possible to split them apart, say and have the bass portion earlier in the circuit?
i'm open to active or passive!

[Hides-His-Eyes]

I don't know specifically but replacing a treble control with two fixed equal resistors would be trivial to do what you want.

[merlinb]

There are some very simple treble and bass controls, and yes, you can position them separately in different parts of a circuit. If you put treble and bass together then it's called a James stack, or a passive Baxandall stack, depending on the details of the circuit. If you put them together and in a feedback loop then it is called a Baxandall tone control.

[caress]

ah ok. i guess i need to do a little more reading. i was looking at the baxandall specifically because it boosts or attenuates, though perhaps the same thing could be done with 2 separate active filters (lpf/hpf) with fixed frequency and variable gain?

[BubbaFet]

 
Read the original passive tone control article by EJ James, from 1949 !
http://www.thermionic.info/james/James_SimpleToneControl.pdf

Then read the active tone control article by PJ Baxandall from 1954 that builds on James work !
http://thermionic.info/baxandall/Baxandall_NegativeFeedbackTone.pdf

[caress]

excellent reading!  the james control is what i've actually been looking at, rather than the baxandall.  thanks for that!

[caress]

after reading up a little more, it seems like some people have lifted ground on a portion of the controls to disable/bypass them, so ok weird idea i have here, but it may work.  i'll hit the breadboard on sunday and see if i can get anything useful out of it...



of those 3 connections coming up from the bottom:
1st is input1
2nd is output1
3rd is input2
(to high impedance buffer) is output2

so the goal here is to have 2 separate controls (bass, treble) that each have a cut/boost and can be switched from one section of a circuit to another.  i am aware of the impedance issues regarding the tone stack, so that will need to be addressed, but i would probably just use a dual opamp and add a buffer to the output of each.

i would completely understand if this doesn't work since it would be changing the circuit network by disabling part of it. 
maybe instead of lifting the ground, a set of 2 resistors approximating the center point of the pot were switched to where the pot is?  hmm