Looking for info on variable cross overs. Akai SW-177

[chinoy]

Im trying to replicate the controls on this speaker.Not even sure what such a setup is called. Whats the technical term for it.
Is there a schematic somewhere that would give me an idea as to how something like this works ?.
If I could get the technical term for what such a setup is I could probably have better luck looking for info.
Sorry for the Noob question.
Have been able to locate some old 15 inch paper cone philips speakers. Want to use this kind of cross over.

https://www.hifispeaker.wiki/item/a...v01k3uBjnFSTPLMVijRTKmbOVZNKwrW_Uf3IOQHKRJ0Yw

 

[AllenB]

Crossovers like those usually either have switchable resistors or contour circuits, or they have variable L-pads.

 

[turk 182]

nothing exotic about a three way with Lpads on the mid and high frequency bands other then it's less common these days make no mistake though those controls don't vary frequency at all just level...

if you want a variable crossover there's many active devices to chose from