Scan-Speak Revelator 18W/4531G01 7" Woofer
The 18W/4531G01 features a non-resonant cone and dust cap structure, dynamic linear suspension, SD-1 magnet system, "Grasshopper" cast chassis with maximized air flow and resonance terminating mounting system. Less resonance in all structures, lower compression and higher linearity, faster termination of excess energy and higher sound pressure capability. The 18W/4531G should have an F3 of about 65Hz sealed and 40Hz vented. Also an excellent choice for high end autosound applications.
Data sheet