High level input to hypex plate amp (UCD)

[yoke]

Hi all
Have look around, did the search, but most come out to suggest to use line level from preamplifier which is not an option for me...

Any way, I need some advice;

the plan is to make some loudspeakers with integrated ''subwoofer''
mid/bas and tweeters will have passive crossover
and subwoofer will be power with integrated hypex psc 2.400
was thinking to use high input to hypex from terminals on passive crossover / loudspeakers terminals

that way, I can use different power amplifiers with loudspeakers
without need to run another par of cables for low input to hypex (so low input is not an option)

here is the illustration how I would like to make it (taken from web and adopted)

Are there any circuit, schematic how to make high to low input for this application ?

Thanks