Yes it is an older thread. JWC had just obtained those subs. Seti, Mark 1101, and I were there and assisted in dialing them in .
There are lots of subs out there but few are musical and have IMPACT at the same time.
With the strait horn trax mid-bass, K402 -K510'a top end....and those subs. All driven by four bridged Mac 275's and two Mac 1.2KW amps??
Being around audio for fifty years I hesitate in saying something like this........... Top to bottom , That was the best audio system I ever heard !!!