My Herron Tube Rolling Adventure continues (and very possibly ends). I'm currently using NOS Amperex 7308's, USN-CEP tubes, vintage 1965. Really nice sound, balanced throughout the spectrum, with airy top end and natural, not boomy bass. The holographic imaging and pace are tops. The system has an ease and warmth without the sometimes distracting midrange presence or mid-bass bloat I heard with the Philips/Mullard/Holland 6922's. Hal-O dampers do provide a smidge of extra smoothness to the top end, without robbing detail. Not cheap, but in my setup well worth it. These are keepers!
I had a talk with Keith Herron about tube rolling. I think the statements in some of the reviews of his gear oversimplify his approach to tube-rolling. I would characterize it more as "rewards can be had, but caveat emptor" (my words, not his). Personally I feel that the VTSP-2 is a well-designed unit with robust decent-sounding and readily available stock tubes, but its worth experimenting with the one performance-altering variable. It's paid off in my case.
I had a talk with Keith Herron about tube rolling. I think the statements in some of the reviews of his gear oversimplify his approach to tube-rolling. I would characterize it more as "rewards can be had, but caveat emptor" (my words, not his). Personally I feel that the VTSP-2 is a well-designed unit with robust decent-sounding and readily available stock tubes, but its worth experimenting with the one performance-altering variable. It's paid off in my case.