Pre- / Amp for Eggleston ROSA

Yes they like powerful amps.

I have a friend who runs a Krell KSA-250 into a pair of Andra 2's with a Levinson front end and they sound very musical, none of the usual attributes associated with Krell sound. In fact, when a Krell amp is partnered with the "right speaker", great music happens. I'm sure there are a few other amps that would work as well also.

so how about those Crown and Hafer kind of rack mount industrial stuff? I think they may still be cheaper than the vintage Krell or Threshold type of pure class A stuff ..