Anyone ever have, use or hear this tube?

@wharfy ,

Yes, I forgot to mention they are coated with a black rfi/emi shielding.

They were made I think for a single specific company. If you did any tube rolling in the Cayin, how did they compare to other, less expensive tubes? Thanks!

Thanks, David.

I have about 14 pair of 12au7 variants. CBS /Hytron one of my favorites.

Mullard CV4003 is another good one. Telefunken red tips labeled for Tektronix equipment, Westinghouse 337 a surprisingly good tube if you can find them, Amperex, Amperex 7316 with ’D’ getter (my favorite), regular Telefunken long and short plates, Cifte, RCA black plates...can’t remember the rest.

The G73R’s would go in a Simply Italy integrated I’m contemplating buying. Last gear I had that the 12au7’s went in was an Odyssey Audio Candela preamp. Gone for a few years now. They're all just sitting in my safe, for lack of a better place to store them.

Yeah, anything labeled for lab equipment and such used the tested cream of the crop. And you pay for those little letters and stickers!

@audioman58 ,

You think you’re the only one with tube knowledge and experience? I’m well aware of where nos tubes come from. They are what I research and buy exclusively. I’m also aware of the common ones, the rare ones and the ones in between. I’m aware of the applicable prices. I’m also aware of reputable companies that sell them, tested, matched, and readings confirmed with a print out. Although I appreciate you taking time to post, your blunt, rigid statements leave a bit to be desired.

Apos Ray 12au7??

Never heard of them, interesting. I'll look them up. I've always exclusively used nos.

@jafox ,

I'm not sure 12bh7's are interchangeable with 12au7's in all applications.

Do you have any insight on this?

@buellrider97 ,

Man, good price!

Yeah, prices have really gone up on the more sought after tubes. Thanks for sharing your experience.