What are the best drop in subs for a 12AU7??

I had 4 Amperex 7316s sold them on ebay few years ago since I don't need 12AU7 for my application. It shouldn't be hard to find but do expect to pay $100 a pair.
Because of lower noise floor, everything sounds better in every aspects of the regular Holland made Amperex 12AU7 with less forwardness.

Contrary to some views, the CV4003 from the 80's is NOT a bad tube. However, it is system dependent, it will sound hard in many. They should also be low-noise, low microphonic tubes too, like from Upscale Audio (no affiliation). Older Mullards, whether CV4003, M8136, ECC82, etc. are sweeter, with a warmer midrange.

From the 12au7's I have heard, late 50's, early 60's Tungsol 12au7 and a little known Brimar 13D5 are very good value tubes. I also like new issue JJ 12au7's, I think it is a nice tube.

Good luck,

I've liked the Tungsram Industrial grade 12au7 from Hungary (dated 1971) available from A'gon member Tubemonger. Very quiet and detailed.

Thanks for all your input so far. The Mullards I own I bought several years ago on Agon and are labled as 12AU7. I do think they sound pretty good. I am pretty sure though that they are not 1960s Blackburns or anything that old. Probably 1970s possibly 1980s. I have to admit I haven't dug them out to check to see that they don't say 4003 somewhere on them. Any other suggestions? Keep them coming! Once again something that is not overly rare or expensive would be preferred. Thanks again!

You might try the very inexpensive (about 30 a pair) but remarkable jj ecc802's.. great balance between European warmth and American detail.