Best Way to Split Amplifier Output Frequencies to Main Speakers and Subwoofer

Is there a decent stand alone active or passive stereo frequency divider that can take the speaker outputs from my vintage receiver and send mids/highs to my main speakers and lows to my subwoofer?   I want to relieve my main speakers from deep bass responsibilities. The crossover frequency should be user adjustable.  Neither my receiver or sub have the capability to do this.


Is your sub powered?  Many subs have a crossover built in.  It might be cheaper for you to buy a new sub.  Part-express sells subwoofer crossover in a variety of price ranges.

Does your receiver have preamp outputs and power amp inputs? Make and model would be helpful.