I have an F2B with a Carver PM 1.5 (1200 watts) for a tight, punchy sound AND an Eden VT300 (300 watt all tube) for a meaty, somewhat overdriven power (not preamp) tubes, sagging transformer sound.
 
Anyone tried a Bag End Q10BX-D (4X10 coaxial) http://www.bagend.com/ cabinet? The way it's advertised, it would seem ideal for an Alembic.

Jazzy:
 
Yeah! What adam said.  I use an F1-X and into a QSC PLX2402 poweramp.  I'm driving 2 Eden 2x10 XST cabs.  The sound is Awsome!  
 
Jacko is using the same amp with an Eden Navigator preamp and also getting great tone.  He is looking at EBS or Mark Bass speakers at the moment.  
 
I know you are in England, but if you want to have a listen to either rig, all you have to do is say so, and you would be more than welcome to give them a try here in Scotland.