Tube rolling for EAR 912

I have an EAR 912 preamp and 890 power amp, as well as the HP4 headphone amp and the EAR Dac 4 (although I generally use my Chord DAVE instead). As soon as I got the preamp I started tube rolling. I tried Telefunken, Phillips and a bunch of other NOS 7DJ8s.  Then I tried some new JJ gold pin 6DJ8s. They all sounded awful.

I emailed EAR to ask why and Tim replied that he found it amusing that audiophiles thought they knew better than he did and tried to improve on his design by trying different tubes. I reinstalled the stock tubes - which I believe are re-branded Sovtek. You know what, it sounded amazing, much better than any of the NOS tubes I tried.

It may be that EAR carefully select the tubes they put their own brand onto. But it did teach me that sometimes it is best to listen to the person who designed the equipment.

Anyone want to buy a big box of preamp tubes?

FWIW this is my experience exactly on my EAR 912 - tried Telefunkens, tried Teslas, went back to the standard tubes. 

I have an EAR Acute which I use large O getter late 1950s Amperex.  They are superior to many of the more modern tubes I've tried (about 15 pairs).  Also, my older EAR 864 line stage sounded dull compared to the Mullard 12AX7 CV4004 and cleartop RCA 12AU7 in the line stage.  It became a different animal too, lush tonality (spot on), super dynamic, super deep bass, extended but sweet highs.  I keep it only as a backup because it did suffer from an opaque quality (not severe, just not high end), lacking air and openness of my current pre-amp.  Otherwise, what a gem to listen to at it's price.