Assertion: subwoofer's speaker | /r/HasProperty | vented passive radiators
Facets:
Source sentences:
text: Set the subwoofers' crossover frequencies to the -6 dB rating of your speakers, and set the slopes (if offered) to 12 dB/octave if your main speakers are sealed-box, and 24 dB/octave if your main speakers are vented or have passive radiators.