Let's roll: what pre-amp tubes should I consider next?


I am looking for some guidance from experienced vacuum tube amp users. I have a Unison Research S6 (most recent model) which runs six x EL34 power tubes and two x 12AX7 pre-amp tubes.

Having gone NOS in the pre-amp section, I've had great results over the new manufacture Tung Sol 12AX7s that come stock with this integrated. The tubes I've played with are the Philips Miniwatt 12AX7s and the Siemens 12AX7s. I like what both have to offer, but there are differences. The Miniwatts being warmer and contributing to an overall more subtle listening experience whereas the Siemens are more precise, producing a sound that has attack, excitement and thrill in abundance. However, I find the latter can be a bit too much in the upper mid/lower treble region some times. Is there another new manufacture (thinking Psvane?) or NOS (Brimar, Mullard, Mazda) that would give me the best of both worlds? Good tone and timbre while maintaining a sense of involvement through speed and attack?

What are your recommendations?

funcrusha


funcrusha
Shuguang Treasure 12AX7LS from Grant Fidelity are the best you can buy. They beat out my Telefunkens in the phono stage. They sound good out of the box but do need 20 hours burn in and sound at their best after 100 hours. They are ultra quiet. I've posted about them here before. 
My favorite 12AX7 compatible tube is the 5751 triple mica black plate from the 1950s by RCA and GE, in that order.  There are several versions of these.  The older silver clip versions are the very best.

Prices are all over the board on these.  I have an abundance of the GE version if you want to give them a try.
I'm a big fan of the Mazda(France) silver plate 12AX7 tubes. They have a beautiful air and sparkle to the high frequencys. They wont have the force and power of the Siemens you are using though. But the Mazda is all about elegance and finesse. 
@mickeyb I'll mention them again. Telefunken ECC83 (smooth plates over ribbed plates) are the best 12AX7 type after the Shuguang I listed above. The Teles are neutral and transparent. The Shuggies have better frequency balance, extended highs, and cleaner, deeper bass.