Phono Preamp Tube Rush

@dhcod   +1  I think that sums up my perspective as well.

Ok, 24 hours later and I embarrassingly now need to confess that I'm not preferring the Gold Lions over stock EH's in the Herron.  At first I was smitten with the reduced noise, blacker background, silky smooth mids and extended bass.  I am now realizing that these sonic qualities came at a steep cost of losing the air and wide-open presentation.  Late last night during listening I became keenly aware that the highs were getting rolled off and the bass was actually bloated.  I immediately rolled Keith's stock EHs back in the pre and ahhhh.....everything was so much better.

Interesting lesson here in the psychology of perception.  I was initially seduced by the quiet and a "different" sound, and it took me a bit of time to realize different was far from better.  I have read many times that it's hard to improve on Keith's tube voicing and It'm seeing that now.  I'm still curious about rolling tubes in the Herron but I suspect you need to get into some nice NOS tubes like Tele or Mazda to move the needle any higher.

I played the NOS game with the vtph-2a and came to the same consensus, specially the bloated bass. Decided to stick w stock on this guy - no worries

First impressions of tube or component changes can be especially nebulous - because anything that the new component sonically accentuates can easily evoke a new emotional response that we can't help but latch onto. This can allow us to experience our favorite tracks in a different light, perhaps even noticing parts of the music we hadn't before. However on extended listening - we may notice the accentuation is really unnatural. We may even go back to our old component and suddenly that "new part" of the music is actually still there, we just hadn't listened for it before because it wasn't actually supposed to stand out, lol. 

Gear or tubes that have a high listening fatigue factor are particularly subject to this phenomenon - and listening to it gets old real quick!

Don't feel bad either, experience can help, but a lot of us (including myself) still fall for this same trap from time to time. 

three-easy, Good for you that you had the intellectual honesty to pay attention.  To complete the experiment, try re-inserting the new tubes after 2-3 weeks using the old set.  See if your impressions remain the same.