Suggestions on SS/Mono Amps for woofer towers

I drive my infinity bass with a krell ksa 100. Does the job for sure.

Texas:

I'm interested in your experience with the Crowns.  I'm looking for mono's for woofer towers of Betas.

How have they worked out?

I have used the Crown CTS2000 amp for subwoofer.  This is an evolution of the same K2 type technology (Class I).  While these amps are very good for the money on the used market, they just did not control the subwoofers as strongly as a very high current Class AB amp.  My Emotiva XPR-1 monoblock is the strongest subwoofer amp I have ever used.  The XPA-1 monoblock is probably the next best thing.  If you have lots of money, the Bryston monoblocks would probably be very good.  Or Parasound JC1.

Big power Class-D they like 4ohms and bass is what they're good at, if nothing else.

Cheers George