Crossover calculation help

[slowburn]

I've been using the pictured crossover for over a year and I like it. Please note that I forgot to sketch in the 1uF cap in series with the 2405.

Previously, I'd used the same 13uF and 1uF cap values on the LE85 and the 2405 respectively, in conjunction with an L-pad to set each driver's level.

When I inserted the autoformers into the crossover, I used two legs of the L-pads as adjustable resistors. When I found autoformer taps and resistor value I liked, I measured the L-pad and found they were each around 20 ohms, so I subbed fixed resistors and all was good.

Let's say I'd like to reduce that 13uF mid- driver cap to the lowest possible value while keeping the roll-in slope the same. If this is rational, what is the math that allows me to calculate that cap's value and the corresponding change in the fixed resistor's value?

[Doctor_Electron]

You want to raise the crossover point of the midrange by lowering this cap's value?

Is that a variable autotransformer? I would like more details, sounds interesting.