What are the frequency settings for a subwoofer? I have a subwoofer with 4 different frequency settings. I need powerful, punchy bass. Should the setting be positive or negative? - Quora
What is Subwoofer Room Gain? | SVS Sound Experts Blog
Tuning your subs
LAB SlapBox™ 1.30 ft^3 Ported MDF Enclosure Box for Single SSA GCON 10 Subwoofer
How to Design, Size & Tune a Ported Subwoofer Box in WinISD for Deep Bass: Home Theatre or Car Audio - YouTube