NOS Tubes - Ecstasy or Agony

The longest lasting NOS tubes I have ever purchased came from Andy. It's worth the wait.

     UPDATE (just a little fyi):  STILL have the same Sylvania (40's/bottom-getter/two hole*) VT-231 and a T/S Round Plate (metal top support), in each of my Cary monoblocks (per my 3-21-2021 post) and they are STILL performing splendidly, far as taking me from, "here" (my listening room) to, "there" (the recording venue). 

     There are a multitude of variables*, when it comes to purchasing vacuum tubes, whether NOS or new production.       PERHAPS, the most important: your individual knowledge/research on the subject.

     It's been my experience: the aural benefits/attributes of listening through a tubed system I value most, are (invariably) best generated by components equipped with NOS valves.

Both agony and ecstasy, as many of you are aware.

Vintage 6SN7 are quite often problematic in preamps (except as follower outputs), due to noise and microphony. 6SN7 are usually totally awesome in power amps (as phase splitter / V1 or driver tubes). The later GTA and GTB variants tend to be much quieter (OK for use in preamps), but have less sweetness to their sound - they do make great KT tube drivers in amps, though. 

I've bought lots of tubes from Brent Jesse and Upscale over the years, both great 99% of the time. They're human, so mistakes do get made (I've had a mistake from each) but these cases are the outliers; both sellers are honest so they'll work to rectify any issue. 

I've also got tubes from Andy / VTS, and they are as advertised; the problem is a lot of his stock is RCA and (in the end) those tubes have never worked out for me sonically. For the better part of a year I had some VTS low-noise selected RCA 12AX7 in my VAC Renaissance SE phono stage, never initially questioning them (dumb). They were indeed very low noise, matched and strong. But the sweetness and warmth of my VAC was all gone. I started to blame the VAC! When I finally got back to rolling in other 12AX7 makes, it was immediately apparent the RCAs were 100% at fault - bright and lean sound, ugh. Thinking back now, I just don't like RCA - sure there are exceptions, but even with those, there's always a different make I like better.

Ebay is a crap shoot, as expected. I've gotten good and bad tubes there, in equal measure. 

The modern Russian tubes are fantastic; the sub-brands each have their own sonic flavor, and they're easy to find in low noise matched pairs. BUT they still don't have the 3D holographic image or ultimate articulation and refinement of the very best vintage tubes. Their warmth seems a bit more 2D and less nuanced, somehow. 

RCA's can sound great. I rolled in a pair of Clear top 12AU7's into my amp and the soundstage increased considerably. One thing I have found is that IF one can source an organ re-brand, which these tubes are ( Hammond) then they are a little less noisy than the original labels. Not always, but mostly.

@daveyf Agreed on the organ pulled tubes. The RCAs black plates and other classic American 12AU7( AX7?) from organs I’ve used have been uber quiet and sounded excellent, but I no longer use them due to system changes (my RP9 preamp uses 6H30s). A plus is that the organ pulls are cheaper than "NOS" and they have been essentially pre screened for low noise and performance. The RCA black plate organ pulls I’ve used are superb as gain and driver tubes.  Also, I can't type "organ pulls" without giggling, sorry.