If you could only upgrade 1 thing on a factory sound system

[omnibus]

Let's say you buy a new vehicle, a cheap one and can only upgrade 1 thing. HU, speakers? add a powered sub perhaps?...what would you upgrade and why?

I think I would go with HU. More features, options to tailor the sound more to my liking and output power would better match the input power of the stock speakers. Then again if I liked the factory HU enough, I'd likely just get a powered sub to add a little bottom end and plus bass is one of the most immediately noticeable things that adds fun to the music even if it's not the tightest bass in the world.

[slowfkncar]

The headunit, if the factory head units got enough output then components. I like my front stage =)

[Ron36]

I would add a sub , something small like a 8 or 10 but I need bass .

[neuspeedescort]

the entire thing.  that counts as one thing right?

[DLHgn]

Probably a sub. Most newer cars have integrated HU's and okay door speaker (emphasis on the ok lol) but the low end is almost always lacking and is usually what causes the stock speakers to give out. 

[Skullz]

The vehicle

Not all sound systems are created equal.   lol

[Wishuponasub]

I saw a guy who had one of the new Nissan Titan XD (Cummins) Platinum Reserve trim. He cranked up the Rockford Fosgate  system that came with the truck and it was quite nice actually.

[Soundfreezer79]

Subwoofer.

[Kyblack76]

Depending on how new,  the low end. If it's silly new, wouldn't touch it. Just enjoy it.

 To much of a pain in the ass to do anything to uber new rigs. And some of em can sound decent enough to not fuck with...