Shall I add a preamp to my setup?


I newly setup a system with Thiel CS 3.7 speaker, driving my Sim audio Titan 5 channel poweramp, source with Simaudio cd5.3, I am very excited with the 2 channel performance, but it seems lack of warmth of vocal and extension of high, not enough airly extensions, base is fine. I doubt my weakest link is the Sherbourn PT-7010A pre/pro, all the above new gear has pretty much break my bank, I wonder if I should squeeze the rest of bank reserve for a descent 2 channel preamp in order to solve the problem.....the other choice is a better CDP, can someone walked thru the similar path give me some advice?
grandetech
Asa, may I know how do you prefer Ken-Rads over Sylvanias?

I just love more and more to my system every single day, the SLP-05 is terrific in all area, hope rolling to the NOS tubes early next day will shine it up even more, I will let you know soon, thanks, ASA.

p.s. I don't mind the hiss at all, the music covers everything even no matter what volumn level. Jazz piano will bass and drums are top notch now...
update on tube rolling, Cary/Gerald has suggests to roll tubes on the buffer stage in priority, follow by the gain 4 tubes, so I am going to put the RCA vt231 pair in buffer stage and with sylvania vt231 to gain stage.

p.s. Thiel CS3.7 is such a revieling speakers, crap in crap out, with Cary tube pre, you get great resolution with terrifc warmth, muscical, I consider this is a true synergy and absolutely in love with the speakers now. I had A/B SLP-05 with SIMAUDIO P5.3RS, absolutely different league in terms of transparency and bass control, everything seems more clearer.
The black glass Ken-Rads, while a bit darker, are very expansive - assuming you get a good pair. The Sylv are nice, but IMHO just a bit less all the way around, just a bit, which adds up, of course.

My choice is the black glass Tungsols, but they are getting very hard to find.

On the Thiels, hey, if you love 'em, great! I mean that!