After buying an amplifier that uses the 6sn7 tube, I did my due diligence and read everything I could find on that tube. I quickly realized that the popular tubes had been bid up in price to substantial levels. So I began my judicious search for good yet affordable tubes. I quickly learned that all tubes of the same age, model and make don’t sound the same; they actually vary quite a bit. I also found out that NOS doesn’t necessarily mean it sounds better than used. Maybe used tubes will die quicker than NOS, but in the meantime they often sound indistinguishable. Also, many tubes are mislabeled or re-labeled with another manufacturer’s name. Non-audiophiles aren’t always up to date on what Head-Fier types are willing to spend, so I found that Ham Radio guys, organ rebuilders and people with a bunch of ‘old TV tubes’ often offer great buys.
Here are some examples of tubes I bought for very cheap. Either because the vendor didn’t know what he had or I spotted a gem through the picture supplied:
Basic RCA GT turned out to have grey glass
2 metal-based 6sn7W’s because they were labeled as 6sn7A
Nice Raytheon WGT with no name company printed on the base
RCA 6sn7 was actually red base 5692
CBS/Hytron “industrial tube” was a brown base 5692 re-labeled GTB on the base
I don’t know if this helps any new tube amplifier owners, but I have found that tube-rolling can be fun, rewarding and not necessarily expensive. Patience can help especially on Ebay. I got a new looking black glass National Union that I paid more for shipping than I did the tube. Just my 2¢.
