Do I need an aftermarket radio or stereo for me car if I get subs?

I'm driving a 2004 Honda accord ex and I want to buy subs but I don't know what stereo or radio I need to get for it. Could I stay with the factory stereo?

Yes, you can keep the factory stereo and add an amplifier and subs. Choose an amplifier with a high-level input feature, or use a line output converter. This allows you to use the factory speaker wiring as the input source for the amplifier.