I needed a passive low pass filter for a subwoofer I just have hooked up to the B channel of an amp. This rolled off the high and mid frequencies well and was economical.

I purchased several crossovers to see best behavior for 3 sub-woofer build-ins to home theaters I put together with my own amps. This was by far the best one I tried for sub-woofers. I was satisfied with 1st try after comparison, and purchased the rest exactly the same.
As an interesting note, when sound-feed applied to it, you can actually hear the sound (sort of metallic), coming from the windings over the core... I just hope it won't eventually friction the insulation away ...
What I did not try was super-high volume... as in public-party... but for a loud home theater with good sub-woofer effects, it was perfect.

BTW... lots of contradicting info out there to sound "fullness". You will have to use two speakers (and two crossovers) to get all sounds in track, rather than just from left or right track -though for deep bass, most tracks will have basically the same deep bass sound in both channels. Thus when doing a 5.1 or 7.1, etc, strictly the bass is a mono-aural source rather than stereo. Now if subs connected to each side of stereo, you would attain 5.2, 7.2, etc.. This is my best understanding of it after much reading and filtering, though some might think different.

As for this crossover, I am very pleased, have purchased more, and used for very small spaces the others I bought, as those seemed more of a woofer type than sub-woofer like this one really did.

One speaker system includes (8) 4" landscape speakers, (1) direct-burial 8" passive subwoofer, and a 1,000 Watt (2x500) amplifier. The second system includes (4) 8" surface-mounted outdoor speakers, (1) hardscape 10" passive subwoofer, and a 1,000 Watt (2x500) amplifier. The source for both systems in (1) Sonos Port music player.

The 1,000 watt amps are IP enabled and can be setup as 8 ohm 2-channel or 70V bridged. The wiring for the landscape speakers is 14 awg, 4-conductor and every other speaker is left/right in series and subwoofer is on left channel. The (4) 8" speakers is also setup as 8 ohm with the passive subwoofer on right channel and speakers alternate left then right, left then right, etc.

As seen in the photos, I added a jumper from the left channel (surface mounted speakers with hardscape passive subwoofer) to a dry-box, then out to the subwoofer. I did add a set of 4 spacers to mount the crossover inside of the dry-box so that the crossover was not just sitting loose inside. Everything is water tight and because the subwoofer itself is closer to the deck than the surface mounted speakers high up on the house, the crossover surpresses the vocals such that they are fairly inaudible even when standing or sitting right next to the sub.

These crossovers are doing their job! Highly recommend!

I installed a 6" woofer in a camp trailer. I'm driving it with a Jensen stereo that has three speaker outputs, and it's wired to speaker C.

The Pyle dual voice coil speaker I used has good bass, but it was also trying to act as a mid range speaker, and sounded like garbage. With two of these inline, (one for each stereo channel) at least 99.5% of the highs are GONE. No more guitars, singer voices, or anything else, JUST bass comes out of that speaker. (As it should be!)

Note that these are bigger and heavier than I thought they'd be, they weigh about 3/4 of a lb. and are about 3 1/2 inches square.

Works great! sound quality excellent no distortion so I had to buy a second pair for that price you cant go wrong.