Radiotechnique 12AU7/ECC82/6189 Sonics

That's the branch of Philips Holland, that manufactured tubes in France. Some of the best(small plate) were made in the late 50's. They made another 12AU7WA(longer plate), around 1965, that was nice tube also. Either should prove cleaner and more open, than most Mullards(even though Philips owned them too). Philips Miniwatt or Amperex Bugle Boys(same company) might appear on your short list as well. If you still want less warmth/ more accuracy; try pre 60's, Siemens ECC82( http://www.tubeworld.com/12au7.htm ).

No one call tell you, specifically, what any tube will sound like, in your system(too many variables). Good luck, trying to find someone that has that kind of experience, with all versions of Radiotechnique's 12AU7's. Radiotechnique has never been what one would consider a, "mainstream" or "popular" NOS tube(ie: Siemens, Telefunken, Amperex, Mullard, Brimar, etc), BUT(who knows)- there may be someone out there, that loved the company's products. Happy listening!