What would happen if I got my speaker wires crossed?

Let's say that I connected positive to negative from amp to speaker instead on positive to positive. What would be the effect on sound quality?

 

I believe sound quality would be very poor and the signal would be out of phase...don't know for sure b/c I made certain the connections were correct. Do you think this is what you have done?

 

You would get almost no bass, and it would sound terrible. Youll be able to tell right away.

Why, did you do an oopsie?

 

My amp is mounted under my seat and I couldn't remember if I made the gray wire or the black wire positive so I guessed.

My fronts are fine but the rears in the S-Pods, although they are doing wonders for rear fill, sound bad when isolated. I'm wodering if I guessed wrong. Could it also be that b/c I was in such a hurry to mount my S-Pods that SQ is suffering since I didn't mount the mids flush?