tube pre amp or tube amp

Yeah, unclear what the OP wants to accomplish. I would probably try Lamm hybrid power amp. Lamm is first of all famous for its power amps. I would not replace VAC with Pass, maybe with another VAC. And I would certainly have and keep tube preamp.

Wahoo, I would do neither, you would get far better results upgrading to a much better digital front end. 

Your  ARC CD 9 is showing its age vs newer digital front ends which will uncover more information and present a more realistic soundstage.

You will be shocked at the overall improvment you allready have an excellent set of electronics.

Other things you can do to improve the system is to use Critical Mass Centerstage footers they difference they make is shocking, you will get far great image width, lower noise floor tighter bass and greater dynamics.

Our philosophy is to tackle the weak points in someones system. and your digital is five years out of date. 

You can go to a much better CD player, a CD player Dac, a pure Dac, you would be amazed at the improvements by adding a digital server and moving into modern streaming. 

You can always reach out to us if you want further information

Dave and Troy
Audio Doctor NJ

I've always enjoyed a tube pre with ss amp combo. I run less efficient speakers so the ss amp makes it easier to drive them.

Previously I had a VAC Renaissance 3 and a VAC PA100 upgraded to a phi front end.  I first changed the power amp to an Ayre VX-5/20 and then upgraded the Pre to the current VAC Renaissance 5. Really enjoying this combination.

i’m a little different in that i have found that a great solid state preamp driving a great tube amp is very special. whether right or wrong going this way adds tube magic as the last link. 
the are many ss preamps that fit the bill and often have better features. fwiw