Best small signal tube for a preamp?


Is there inherently a "best" small signal tube for use in a preamp? Assuming all other things are equal-which of course they never are.
Choices are 6922/12AT7/12AU7/6BK7/6BZ7/12BH7/6H30II (and varients to the listed tubes - e.g. E88CC for 6922, etc.).
The reason for my question is that I am auditioning the Lector Zoe, which can use all of the above tubes by way of its SATC ( autiomatic tube adaptation) circuit and user switchable 6V/12V plate voltage.
I am interested in your reason, which might have to do with inherent sonic characteristics, predisposition for problems such as noise or microphonics, or availability and economy of NOS tubes being better for one tube type over the others. All responses are welcome, and in return I will let you know the results of my listening with the different tubes that I try.
mitch2
Keshiri, I didn't realize your Zoe came with the 12AU7's. Mine is the newer model with black side panels (a recent demo) and I believe it came with the EH 6922's. Brian at Aaudio said they have upgraded some parts in the newer model, but Lector always seems to be behind in the documentation department, so I don't know which parts. Anyway, with the PQ White label 6922's in my Zoe, the sound is fantastic in a very musical sort of way, with a full rich midrange and excellent bass, but maybe giving up a small amount to the best I have heard in the high frequencies (probably not a fault of the tubes). I do not have 12AU7's in the house, but I do have a small variety of 12AT7's I have used with the CDP 7TL. In general, I like the 6922's better in the Zoe than the 12AT7's, even the stock EH 6922's sounded pretty good - no less clear than the PQ White's but not as rich and without the quality of bass texture.

In the CDP 7TL MkIII, which only accepts 12AT7's, I have to say I like the RCA triple mica black plates I purchased from Brian the best, expensive though. I also liked some NOS Mullard's I tried, but not as much as the black plates, which display superior clarity and extension. The US Jan white label Amperex 7308's you are getting are also supposed to be a pretty good tube, let us know how you like them.
You're right Mitch- If a piece of equipment is already too bright or forward sounding, the CCa's might be too much(like a lot of cable mis-matches). I've found with the BAT VK-D5, CCa's and a pair of Kimber Select 1130s: everything encoded on the disc makes it to the rest of my system(nothing added, nothing missing). Great at reproducing the depth and width of the original recording venue's soundstage as well. This is what "tube tasting" is all about.
regarding the Zoe on tubes please remember the regular Russian 6h30 tube unless very closely matched can be as bad as a 6922 Sovtek the Best 6h30 which is very good is the DR designation this are the creme de creme scientific
grade and run at over $50 each I compared them and for sure they are very good and just a hair warmer then neutral.
lector zoe fans want to know where the best deals are on the 6H30 DRs.

thanks for any help. -ad