I've used an NHT x-2 in the manner that Kal suggests with an Veolynse SMS-1 for sub EQ and integration. The good news is that both x-2 and SMS-1 are reasonably priced (if you can find an x-2) and work very, very well, but ....
This is a giant PITA to set up properly and a bit of a kludge on power-up. I eventually switched to an Audyssey enabled prepro and am very happy with the results. I understand the desire to hang on to a nice piece like your Classe preamp, but I replaced an ARC pre and a Joule pre with an Onkyo prepro and have never looked back.
FWIW the anti-mode that Kal suggests will likely ease the set-up issues presented by the SMS-1, but at IIRC twice the price.
Good luck
Marty
This is a giant PITA to set up properly and a bit of a kludge on power-up. I eventually switched to an Audyssey enabled prepro and am very happy with the results. I understand the desire to hang on to a nice piece like your Classe preamp, but I replaced an ARC pre and a Joule pre with an Onkyo prepro and have never looked back.
FWIW the anti-mode that Kal suggests will likely ease the set-up issues presented by the SMS-1, but at IIRC twice the price.
Good luck
Marty