Tweaks That plug in to speakers and ? Why they work

Oh geez, I'm financially challenged. Back to the OP, please!

The filter can only take away, it can ADD nothing, that’s why it’s a filter.

Impedance matching is going to cause the onboard XO to act differently, or correctly via the way it was built and tested, either more so or less so.

I can see why quality parts don’t sound WORSE, I just don’t get how they sound better?

There must a funky factory XO, that a (shot in the dark) filter makes everything sound better.

I’d pay a little more attention to what Erik is saying OP.

HF roll off will sound better if the room isn’t treated. Mid or BASS, it depends on what the filter does. It may, and most likely does, make the ramps a LOT steeper, so they sound sharper.

Dips are going to stay dips, but peaks, steeper roll offs and a lower frequency roll off is what that filter CAN do.. It can’t add a thing..

Cheap parts in the path.. vs quality parts in the path vs NO other parts in the path. I’ll go with room treatment, tone control and NO extra parts in the path. :-)

Time to feed the Chickens...

Regards

Mercy gentleman.

The happiest woman/man I ever met was rich.

The happiest woman/man I ever met was poor.

The same with the children of these people.

They ALL had one thing in common and it had nothing to do with their monetary situation.

They kept their personal and spiritual life in good order. The TWO worked together like hand in glove.. :-)

Regards

Parts quality is so important, I once bought a tweeter upgrade from the Linaeum speaker designer himself. Heard it on my speakers in his design studio. It required a different crossover that he showed me exactly how to build. One resistor, one cap, very simple. Bought the exact parts at Radio Shack, hooked it up, immediately called him up wondering WTF is going on this sounds like crap nowhere near as clear and detailed as what you did!

After some questions to make sure I did it right he asks what parts? Radio Shack. "That’s your problem." So I ordered new parts, exact same values, and instantly heard massive improvement.

The way it works, parts are measured under static load conditions. Music is never static, it is constantly changing. Frequency, amplitude, swinging all over the place all the time. Only way we know to "measure" anything this complex is by listening.

This is exactly the same as the way everyone has 120V AC, or 100 watts per channel, or .3mv output, but yet everyone’s AC, amp and cartridge sounds different. It is all the same, only for some reason hardly anyone seems capable of seeing the patterns.

I think I know the reason. One of em anyway.
https://youtu.be/9oJdG8THofA?t=108

My tech told me these purifiers are a filter which = cleaning 
high frequency hash or noise that absolutely rides about 12 khz typically ,and can be measured removing the noise does drop 1-2 db , but when taking a spl meter and matching output you can for sure hear better separation   and depth of image which effects the 
whole upper end , they do take time to runin , much better then the low quality build synergistic type.