Its line level, so clearly, one would need to hook this up after the source/before the amp, with typical rca jacks.
It would save the trouble of wiring up an attenuator as it has its own gain control, and also has an adjustable 40hz-150hz low pass (vs. seperate ones) .
I like that its not active, but it seems awful cheap.
I always thought passive crossovers were typically MORE expensive than active ones?
Also very tiny.
Makes you wonder if its really stereo, or the manufacturer mono wired the inside, which would suck for flanking subs.