When a company says that their 4 or 6 ohm loudspeaker or driver handles say 100W, is that 100W at the nominal impedance, or 8ohm? To further illustrate, if Seas sells a tweeter that’s 4ohm and handles 50W, is that 50W into 4ohm (only 25W into 8ohm) or is that 50W into 8ohm (100W into 4ohm)? Would be a lot less confusing if they rated it in Vrms.