They say that since the bass amp relieves the main amp of those duties that selecting an amp is easier. I found the opposite with my 350's and needed a strong amp just to keep up to the bass without a "hole" in the midbass. A Plinius SA-100 served well. The 500 is even tougher, with a fairly low impedance dip.
For tubes, consider VTL MB300/450's or Manley Neo's. Used to do a lot of shows together.
For tubes, consider VTL MB300/450's or Manley Neo's. Used to do a lot of shows together.