I would suggest addition of another amp for bass drivers, i.e. trying bi-amping. Natural choice in this context should be the Primare A33.2 (120Wpc).
Having pretty extensive experience with B&W (not exactly 803D, but smaller 803S - used to own them for 3 years), I have not impression that I30's current capability is sufficient for always power hungry B&W. My former pair of 803S sounded properly with Rotel RB-1090 or Parasound A-21, much bigger amps than I30.
Having pretty extensive experience with B&W (not exactly 803D, but smaller 803S - used to own them for 3 years), I have not impression that I30's current capability is sufficient for always power hungry B&W. My former pair of 803S sounded properly with Rotel RB-1090 or Parasound A-21, much bigger amps than I30.