I recently purchased 2 U15s and ran them off a Wolfram 3000.1. One of the subs locked up within a week. Box built to spec and gain set with SMD.
Anywho..I have sent the locked sub in on an RMA as of 8/3. I am interested in having it rebuilt with a stiffer spider and 8 layer VC. I would gladly pay the difference in cost if parts. I would also like to send th good sub in to be rebuiltin the same manner.
I have emailed several of the Sundown contacts about this with no reply.