What can i do to make my tube preamp sound warmer?

I have to disagree with the others about silver interconnects. While copper may sound better in your system, silver is not typically bright and lean sounding. I think when people first started expeimenting with silver cables this may have been the case, but with years of research and trials, silver cables being manufactured by many companies are now equally as smooth as copper.

On the other hand, I have to agree that your speakers are probably the culprit in your system.

I tend to agree with Elgordo and the others that the speakers are likely what is causing your problems (it could also be room acoustics), and no tube change or interconnect change is going to remedy the shrillness you hear. If you can borrow a different set of speakers to try in your room, that might be helpful for you to see if the CVs are the problem.

Changing your 12ax7A's to warmer ones may help-what do you have now? I would say that amperex tend to be a little warm for me may just take the bite out of them?

I agree that silver interconnects don't neccesarily sound bright and shrill, blanket statements like that serve no purpose.

Hello,
I have gone through many interconnects and have learned that a good balance of silver and non-silver is the way to go. SilverAudio makes a great line of cables but I found my system fully loaded with these was indeed too forward and analytical ... particularly on the top. A couple of Cardas Golden Cross to/from the line stage helped a lot. Too much of the CGC and the system lost detail and too much of a good thing in the mids. It truly paid off to try diff cables at each link in the system and weigh the pros/cons of each to get a well balanced result.
But I would suspect that auditioning other speakers might be a more viable solution than fussing with cable at the moment.
John