Yeah! I'm happy there's at least one other guy in this forum who's got the idea. Basically, I wouldn't even want to claim I could tell an "inversed" bass from a non-inversed one. But your hint goes in the right direction: strong pulses. A strong positive low frequency pulse, immediately followed by high frequencies of low energy simply draws a different picture in my head than the same sequence started with a negative pulse. There's no right or wrong, it's just different. The explanation is that within a certain range your ear is converting mechanical energy "symmetrically", that is you can't identify a constant sine wave of being started negative or positive. Even more, with listening long enough - and long is meant to be in the range of microseconds - your ear will sum up any a-symmetric influences to just one let's name it average hearing experience. Things become different, though, when your ears are reaching a range they can't cope with, when there are no (or no close) signals of the same amplitude but opposite polarity to compute an average value from. If you ever have the chance to lift yourself up a 100 floors in a fast elevator - mouth and nose shut - and then back down again you might understand what I'm talking about: It even HURTS different.
