Which one better choice?

ARC SS amps are generally designed to work well with tube pre-amps, since that is ARCs specialty, so I like the idea of going with a company that addresses use with tube gear well, and ARC is ALWAYS a rock solid choice.

.(( this amp has an input impedance of 22kohm))
Rings out more like 15 k, would work but not ideal.
Most tube pre amps operate better up at 100K input imp.
Like I said any CJ amp or ARC amp will fit.

Thanks, George

Your CJ-PV9A has an "Output impedance: less than 200 ohms" this is average and could rise a little at the extremes, this is quite good for a tube preamp, and should be suitable to drive most low input impedance poweramps I would say down to 10kohm.

So look at the input impedance of whatever poweramp your thinking of and make sure it's higher than 10kohm and pick your poision.

Out of the two you mentioned above I would go for the X-250 as I've always been a follower of NP, this amp has an input impedance of 22kohm so it would be good with your CJ preamp.

Cheers George

Thanks , for your suggestion.

Any ARC solid state amp would work
100.2 would work has a more friendly input imp for the CJ pre amp amp interface matching.
JohnnyR