I'm searching but i can't find a definitive answer. I don't even know if there's one. That said, and i will probably be happy with whatever i end up buying. Because to be honest, i don't think my hearing is all that great and it's not trained like a lot of people here. So for example, even if they say the Variations are not good (or ideal for metal i rock) i think i would enjoy them a lot anyway. I don't really know what to do, ahahaha.