seeking please, cheap crossover options for 2 channel powered studio monitor PC setup?


I'd like to get a sub$500 unit new or used for the following application;
-vintage powered speakers (I don't like how they handle bass below 80hz) that I will connect to a desktop PC and Dragonfly dac using an old vintage receiver as a pre amp, with external powered subwoofer

-ideally, the cross over unit would eliminate the need for the receiver
I'm not knowledgable enough to ascertain the differences between some of the analog units at pro audio shops, the digital units, and something like a mini dsp
thanks in advance




audiocanada
forgot to add, would a used AV receiver with preouts be an option worth considering?
also, if anybody has a recommendation fro a vintage receiver or preamp that has high pass filters controls on the front this would work too

finally, I'm willing to get a pro style subwoofer also, the type that allows you to use send a speaker signal in, crossover in the sub, and then send the signal back out, these subs are plentiful and cheap and yet made by good brands such as Dynaudio , JBL, Adam, etc.....and would accomplish my task