Frequency Range calculations for Poly Moog Resonator

widdly

I want to build a polymoog resonator but with 4 filters instead of three. I have a nice enclosure from a 4 band parametric eq that I would like to reuse.

Do you think it would work ok to just duplicate the middle band or would it be better to shift all the bands further apart?

Any suggestions for what value capacitors to use?

Also, I tried calculating the frequency based on this page...

http://www.daycounter.com/Filters/StateVariableFilters/State-Variable-Filter-Design-Equations.phtml

.. So I figured I could calculate the frequency range using..

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Using R1 = R2 = 12.4x10^3 and C1 = C2 = 68x10^-9 I get w = 1186 which would be 187Hz

Using R1 = R2 = 2.4x10^3 and C1 = C2 = 68x10^-9 I get w = 6127 which would be 975Hz

Is that the correct way to calculate it? My results don't tally with the ranges on the front panel of the original moog.