crap. i didn't have any spare drivers to test the XOs with before i shipped them back, but i triple-checked the wiring and didn't see anything weird. originally there were some major wire-routing differences between the two when i found a better way to do the second one, but i went back and made them essentially the same. can't help thinking it still must be something i messed up, though. :scratch2: do you have a DMM with continuity-testing mode? that's a first step to doing comparisons between the left and right tweeter circuits. the layout is simple: from the positive post to the fuse (have you checked that?), then to the 12uF cap marked "T", then it branches with the teeny inductor shunted to the negative post and the other wire going to pot and then to the tweeters, with the return wire from the tweeters going back to the negative post.