Best 12AU7 Type Tubes for a Preamp

Tube’s sonics will perform differently depending on the circuit. What preamp are you using?

RCA blackplates, Mullard boxplates, and Amperex 7316 are all excellent tubes but have different sonic signatures. What type of sound do you seek; warm, lush, neutral, high-end extension?

The Amperex 7316 is a premium, in-demand tube and fetches a high price. That would be my blind recommendation, airy highs, dynamic, lush midrange, and 3D imaging. When buying NOS, only use a reputable dealer that publishes test results.

I'm not familiar with your preamp, so it is tough to make suggetions, as many tubes sound different in different circuits.  I will say the best 12AU7 variant I have used in any of my equipment has been the Telefunken ECC802, but I think what you might want to do first is decide what it is about the sound that you want to change, then perhaps ask the manufacturer if they might have some suggestions.  Andy Bouwman at Vintage Tube Services is excellent at helping with this as well, as long as he is familiar with the preamp, if you decide to go the NOS route.  

Plus 1 @lowrider57  

and Telefunken can sound really nice as well. The only tubes I’d stay away from are the lower end Electro Harmonix. Didn’t like them at all!

Just be careful who you buy from.   There is a dwindling supply of NOS 

I recently  bought a quad of early 50's RCA 12ax7 and 12au7 and they were not cheap.   Exactly as advertised,  they are true NOS  and test high.  

I recently bought a tube tester , those tubes were exactly as described but I learned that several tubes that were "NOS"  simply were not 

New production tubes were not exactly all that great. Some triodes were so far apart from being matched they are useless .   

Now nothing goes in my gear until I fully test and confirm they are strong and tightly matched 

New JJ gold pin 12au7 are very good.  

The prices you list for two of the three nos tubes is excessive.

The RCA cleartops shouldn’t be $40 each.

The Mullards go for around $175 a pair, unless they are the m8136 variant. Then they’re around $250 a pair.

If you can find a strong tested pair of the Amperex 7316’s (the earlier the better) for $150 each, I’d get those in a heartbeat.