Would like some opinions on tube rolling


My AudioNote preamp uses two 5687 drivers and two 6x5 rectifiers (I think that's what they're used for...). They are all Phillips. I would like to get a little more bass and mid-bass oomph. The unit is extremely detailed and transparent currently. I'd be willing to sacrifice a little (very little if possible) of that transparency to get the added warmth. Since many here have had good things to say about interactions with Upscale Audio I sent off an inquiry to Kevin, but haven't received any response from him yet. When I do talk with him, I'd like to have a little more background as to the possible alternatives and some input from those who have actual experience with the subject.
Thanks for the input
ekarg
Yup, got a Sylvania in there now, and seems very quiet for a tube linestage, though not as quiet as my passive:). I love the MT 2A, a very thought out product with zero BS factor. As good as my CAT, Lamm, and Joule Signature Edition? Hard to say since I don't have them for a/bing, but I don't feel I'm missing anything, though I would say the Lightspeed Attenuator is still the best "preamp" I've heard with my amps and speakers. I'm going to stop worrying about the 6x5s, but 12sx7???
Have a pair of nice NOS JAN CLRV 12SX7GTs in my MT right now - smooth and relaxed, yet still detailed. Going to try a pair of NOS Sylvania 6SN7GTAs (chrome tops) next.