subwoofer advice

Hey all, I've got a couple questions that may be stupid, but hey gotta start somewhere. I've installed a amp and sub in my car. Skar amp 800w with a skar 18 1200w. My first question is setting my gain. I don't have any fancy tools so it's gonna be set by ear. My question is how do I really...

Hey! 😁 This is my first ever project in car audio! So, first of all which one would be more rational: one big sub or two small subs? (I'm looking for a proper subwoofer experience!) Currently I'm thinking of getting one big subwoofer, at the moment I have chosen the Hertz SPL Show SS15D2. ( Link...