I got it running. I use a teensy4.0 as digital filter reading the analog signal from the ADC do the 2way crossover network in the teensy and send the result back to the DAC.
Startup Time is about a second.
All is powered by a AAMP60 that drives the speaker chassis.
Only thing left is a plopp on power off.
Anyone knows how long I have from the detection of power-loss until cut-off for the speaker? Need to prevent that plopp as it will kill the chassis some day.