Bass boost is nothing but a fixed band of equalization. Meaning there is an equal opportunity to damage your subwoofer by boosting the equalization in your headunit as there is with bass boost. If "you want more", boosting the EQ is the wrong way to do it. Give us more details of your system (vehicle, subwoofer, amplifier, enclosure size/tuning, sub enclosure location & alignment, etc) as well as the method used to set the gain and any other settings you may have. There may be other, and better, things you can do with the current system to get what you are after without resorting to boosting the equalizer. Also, what exactly are you looking for? Simply more output overall? Better low frequency extension?