I believe the best and most reliable are Mil Soec Mullards,
Rare and expensive, You will need to find a hoarder.
Mine were in the box wrapped in paper. They are all tested in an active unit before being wrapped.
Best 12AU7 Type Tubes for a Preamp
I am hoping for some help finding good quality and good sounding 12AU7 variant tubes for a preamp – I need two tubes. A price of around $100 each or less would be great but I would pay a bit more (150 ea.) for something that is likely to sound better. The unit came with JAN PHILIPS ECC82 (12AU7/5963) and I also own a pair of reissue/new Mullard ECC92 tubes. Both sets are quiet but I am wondering if there is something even better sounding at a moderate price.
Readily available NOS options I have seen include:
- NOS RCA Blackplate or Clear Top at about $100-150 EA.
- Amprex 7316/ECC186 at around $150 each, and
- Mullard CV4003/12AU7 $150ea.
New options I have found (in addition to Mullard) include (among others):
- Genalex - Gold Lion B749 / ECC82/12AU7, $70 ea.
- Psvane 12AU7-S Art Series ECC82, $55 ea.
Thanks for any help.