Wilkie – Thanks! “The “B” pots are a linear taper. Adding a resistor across lugs 1 and 3 is adding a linear resistance to a linear taper. Therefore, the resulting taper is unchanged. Only the resistance value changes to @25K.” When I tried this with a linear pot, my measurements seemed to indicate a different taper than linear. Perhaps my plotting was off.
I haven’t gotten to the point of firing it up much less populating the PCBs. I’ still in the planning stages and before ordering the parts, (I don’t stock concentric dual-gang pots), I wanted to answer the questions floating around in my head.
And yes, the resultant difference is audible between “B”, “A” and “C” tapers as tested in other tone circuits. In my experience, “A” tapered pots will reverse the curve when a resistor is laid across lugs #1 & #3. Again, just going thru discussions in my head before committing to a specific build direction. And as always, will socket and see before boxing is completed.