I'm currently driving my Platinum Mk II's with Antique Sound Labs' Hurricanes. I can get plenty of volume with these tube amps. The ultimate would be Balanced Audio Tech's VK150SE's or Carver's Silver 7's, but I think they are overkill for the speakers. I have used Carver's 7t's and 4.0 amps. I used a smaller VTL for the while and that's when I moved to tubes. Good luck.
