My 05 Xterra flat wall. 4 DC Audio custom M1 lvl 6 18s. Tuned low-ish and an absolute demo machine but has still been 160dB@37hz Termlab certified on 20kw : r/CarAV
Paradigm® | In-wall subwoofers
RW-5802 In-Wall Subwoofer | Klipsch
What do u mean by 'wall' ?? | DiyMobileAudio.com Car Stereo Forum
Hows and Whys of Baffle Walls - QSC Cinema Blog
Subwoofers
RW-5802 In-Wall Subwoofer | Klipsch
Revel B28W Passive in-wall subwoofer at Crutchfield