So in conclusion, the problem is not a lack of mid, but the bloat from the DTEC on bass to mids that made it feel lacking. A 2nd order lowpass on the DTEC has helped to tame that very nicely, and even without any filtering on WBFK or CI, the sound is already all that I want from this!
Tuning can be achieved by putting a 10ohm variable resistor on the first resistor position, and that controls the bass relative to the rest. I'm hovering around 7.5ohms for extra clarity in the mids while losing a little bass. The other is a fixed resistor 5ohm.
For those electrically inclined, here are some simulations that confirm my tests.
This is the electrical diagram used to simulate in orcad cadance (pspice)
Green = 2nd order lowpass, 10 ohm first,followed by 5ohm
Purple = 2nd order lowpass, 5ohm first followed by 10 ohm
Red = 1st order 5ohm lowpass
Violet = 2nd order, 5ohm x2.
For the results
Red, the first order is quite inadequate to deal with mid-range bass, with too slow roll off and causing lots of bloat.
Violet, 2nd order with 2 5ohm resistors seems to have much better roll-off at the expense of some signal.
Purple and green are 2nd order with the 10ohm resistor varying in position. While band-pass range remains the same, the roll-off is faster/ cut off frequency is lower if 10ohm is first rather than 5ohm.
Edit: wrong snip
Edited by vector1 - 6/30/14 at 9:47am