Stupid question

Red is only positive if hooked up as positive, and if left not hooked up to anything, it's nothing at all.

do you know if any of your components in your system invert phase?

Typically Red is HOT in an electrical circuit. In audio, Red is considered Hot and the Red from the amp should be connected to the red for the speaker, UNLESS your amp, or Pre-amp Inverts the Phase, then you want to connect the red to black and black to red to correct the inversion of phase from the upstream component.

It doesn't matter, so long as you connect positive on the amp to positive on the speaker and negative on the amp to negative on the speaker. Kind of like jumping a car battery, but less dangerous if you mess it up.

If you do mess them up, it can sound bad. I have no idea why. Since the signal is AC, it's negative voltage some of the time and positive voltage some of the time, so it shouldn't make any difference. But I have heard them connected wrong and for some reason it does sound terrible.

Out of phase speakers do matter...it's all about "suck in or suck out" and if out of phase they "suck in" and that sucks.