Best 12AU7?

I'd also say my 2nd in line behind the La Radiotechnique are the Brimar, CV 4003 gold pin. Its a heavy sound that is totally enjoyable. 100% opposite of the LR 12au7wa - they give my DAC a completely differnt perspective. That's what makes this fun... all the "better" tubes play great, they just come at you from differnt angles & give the presentation a decidely contrasting sound. 

I find it bright, but in a very nice, warm and fat way!

That seems like a contradiction in terms?

I call it fat because of the way it spreads out the sound. I call it warm because of the overall harmonic saturation. But it is basically bright, but more of a creamy, smooth bright!

olds1959special

As already mentioned, reach out to Brent Jessee.....he's the best tube provider I've ever used. He carries a great stock of tubes, but he doesn't give them away. The best 12AU7 tubes are expensive, so be prepared

STAY AWAY from re-issue tubes, go with NOS only

For emphasis on treble (as you indicated) I'd look at: Amperex (Holland made versions) 7316 1950s/1960s, Amperex E800CC/6085 (check with your amp manufacturer that these are okay to use), RCA "black ribbed plate", RCA "clear tops", German Telefunken ECC82s but these are really expensive.....I have only 1 pair.

@olds1959special 

I just bought a PS Audio preamp that uses 12au7’s in its input section. I put out a

some feelers and was given advice from A to Z. So far I’ve tried the PSVANE Art Series, the New Release Tung-Sol  the Gold Lions and some NOS RCA Clear Tops.

To my ears, The PSVANE Art Series were just okay. The Gold Lion were definitely better. The Tung-Sol and the RCA Clear Tops are definitely the best so far, but I want to give the top three tubes 100 hours of play before I A/B them again.

BTW, what are you using them on?