Replacing my Krell FPB 600 amp with a tube amp

dweller......100% correct !!!!                                                                              

gerorgehifi.....REALLY !!!!!!! "YOU"BE BACK" ...........Meaning ill be back to the Krell FPB 600??

Meaning ill be back to the Krell FPB 600??

And others as good and better.
Your 800’s are a pretty nasty load from 200hz down where most current will be needed, 3ohms and up to -55 degrees of - phase angle, this can equate down to around <2ohms in the bass areas as seen by the amp.
https://www.stereophile.com/images/archivesart/88B800fig1.jpg

Trouble with Bi-amping, the internal xover of the 800's is right in the very sensitive area to the ear middle of the lower mids at 380hz and will be sharing this area with two amps, they better be similar in tonal character otherwise it will sound disjointed, as Almarg has also briefly pointed out.

Cheers George

George.. Thank you for the info. Maybe i would of been better off with this thread in the speaker forum. One thing i know is that i will be keeping these speakers. I will tell you that the Krell FPB 600 cruises with the B&W Matrix 800s. But i was just thinking how a tube amp would sound and be with these speakers. And i never thought of it sounding disjointed bi amping until you and Almarg briefly pointed out. Being all that said maybe id be better off keeping my Krell matched to my 800s. 

The technical guys, Almarg, Eric and a few others are invaluable to this site. If you love these speakers as you say, the advice from these contributors can be helpful in keeping you from making a bad choice.
Had no idea the CAT amp had such a low impedance.