It is underrated by about 100-150 watts rms, according to a JBL representative I talked to. Not an audible difference though.Originally posted by Mark_ab The lack of options on it, comparatively speaking. Lack of a subsonic filter being the main one. The XO'ver isn't amazing on it either. The amps aren't really underrated either. They put out (usually) exactly what they say. If they are underrated, it's not by a lot, 50watts or so.