Lamm L2 Reference tube recommendation

Oneobgyn, somehow I think $140k for you is more an issue of will than wallet.
:)

Vladimir certainly designs some excellent gear. No argument from me there.

My mantra has always been "let our ears and wallets guide us". Having said that I just would not (even if I had that kind of coin) shell out that much money. To have heard the ML3 amps however is almost like having an out of body experience

I feel guilty, I never tried that in my L2R but I am interested in your results

I rolled some RCA 12AX3 in place of the stock Sylvania 12AX3. I thought I detected a slightly more natural presentation with less grain, but I could be fantasizing. The difference was not profound by any means. Nothing like what I experienced when I installed Mullard tubes in the LL2 Deluxe in place of the stock tubes.

The thing is there is swapping signal tubes and swapping power supply tubes. The LL2 is a tubed pre with a tubed signal path. The L1 and L2 are solid state with tubed power supplies. So in a well designed circuit, there is less of a difference with swapping tubes in the ps.
But in my case with the L1, the difference was easy to identify albeit small.