Ahtoi, are you sure about this?

I think it does make a difference--if the polarity is reversed the speaker woofer/cone will play inverted rather that pushing out.

On tweeters and smaller mid range speakers you may not hear the difference at low volumes when the polarity is reversed, but if you have woofers and mid ranges that are playing at higher volumes with more bass, you should be able to hear the speakers distort and it sounds horrible.

Maybe OP got lucky when hooking it up, but I still think it makes a difference, but I could be wrong as I haven't tinkered with speakers in a long time. When I use to install car audio 20 years ago, when the polarity was wrong, we new immediately as the woofer would sound horrible and the speaker would play inverted rather than pushing out.

-Lee