I am using the sms-1 between my preamp and power amp. Does the sms convert the analog signal to digital, do the high pass filter and then convert back to analog for output to the power amp (a-d-a)?

If I used the "thru" inputs and somehow used an analog active or passive high pass crossover/filter between the sms and the power amp, would this remove the a-d-a conversion?

I have tried a few variations on the theme, but it seems everything sounds best using the regular setup of doing a high pass filter for the main speakers irregardless of the a-d-a issue. But wondering if anyone has gone further?