In the making, 4th order bandpass to house a JBL GT5-12. Removable/Interchangeable... - Fat Sound Customs - Specialist Custom Built Bass Box Subwoofer Enclosures | Facebook
First HT Sub JBL GT5-12 tuned to 18hz | AVS Forum
JBL GT5-12 Datasheet | Manualzz
JBL GT5-12D | Sub Woofer Speakers | Croooober
JBL GT5-12 Subwoofer, 300 mm von JBL, http://www.amazon.de/dp/B0017P0OQM/ref=cm_sw_r_pi_dp_NWYmsb05M735K | Elektronik, Massiv