Please don't slam me for wanting new tubes, but I get tired of chasing NOS. It seems that the hardest tubes to get as new in the 12AX7 family are 5751s and 12AY7s. For 5751s, there is no choice but Groove Tube 5751M mullard design reissue. I'm not sure about this, but Groove Tube appears to be an OEM, not a manufacturer. If anybody knows who manufactures which of their stuff at what plants, that would be interesting info. What's of greater interest to me, though, is does anybody have experience with 12AY7s from both Groove Tube and EH? Groove Tubes cost more, are they worth it? For all I know they may both be identical tubes made in the same factory with different brand names, but then again they may be very different. :BEER Cheers!