In my limited tube buying experience i have come to the conclusion that brands ,regardless of tube type,had a "house sound".
For example,RCAs were very,very warm with big and often bloated bass. If you wanted a more refined version of that sound you opt for Mullard.
On the other end of the spectrum you have brands like Telefunken,which were quite bright and airy.
IMO if you get to understand the house sound of a given mfg then I think you can safely buy any given type that your amp can take knowing what sound you will be getting....generally speaking.
Other members with way more experience than I with tubes agree with this mindset. If your tube seller wont allow you to choose a specific brand then you need to find a new tube broker.
You can only make that statement for a few select tube types and even then, it could be wrong. Tube manufacturing was quite incestuous back in the day - and even now, too. Manufacturers might make an entire series of tubes, but then not others. Just so that they would have a full lineup for their sales and distribution, they'd buy unbranded tubes by the thousands, then brand the tubes, box them, and sell them as their own. This happened with GE, RCA, Tung Sol, Sylvania, etc., etc.
Some tubes were made by almost every manufacturer - like the 12AU7. That wouldn't stop them from buying 12AU7 stock from another mfr if they were short during some periods.
What you really need to look for is construction. Some mfrs had certain methods in the way the plates were formed, or the getters were made. Others would etch the glass - a much more permanent method of marking than a painted-brand. GE used a series of etched dots; RCA used a squished octagon that held the tube type designation - it was etched, not painted. That said, there are instances of mfrs such as GE and RCA etching sub-contracted tubes, too.
Some tube vendors reference number codes on the tubes. These are useful, but there was nothing to keep a mfr from re-coding and these days, they're often the first thing to rub off on the tube.
When it comes to NEW manufacture tubes, things get even murkier. There were basically only 2 tube mfrs left outside of Asia, New Sensor (Electro Harmonix) and Sovtek (JJ). Since 2012, they're all New Sensor. This guy owns both: Mike Matthews. Like the Chinese in other industries, he's been busy buying up the trademarks to once-familiar tube brands. Certain things are done with the construction and quality to create a perceived difference, but NEW manufacture TungSol, Mullard, Genelex, etc. are all New Sensor (same as either JJ or Electro-Harmonix).
Those non-used tubes made in the 30s, 40s, 50s in their original box are also called NIB.
Been in this business for over a decade - bought, sold, and tested a couple of thousand tubes, but never heard of NOS tubes called NIB. As others have stated, they're either genuine NOS or they're not. Boxes are superfluous. You can buy egg crates of 100 tubes each, without a single tube box and they can all be genuine NOS ... or
not. Also, anybody - anybody can take a tube and put it into a box. Who's to say what's really "original" (see the first reply above)?
It's one of Garage 1217 amps, so it supports almost any reasonable dual triodes.
In terms of tubes, I am looking at stuff nobody wants e.g. 6BQ7A. The ones I got so far sound "fine" to me.
Tubedepot states: "This is a suitable replacement for any 6BQ7A / 6BZ7 tube type. Various brands.".
Who is going to buy "various brands" blindly - television repairmen?
Yeah, exactly. I don't want to shell out for stuff like that and overpopular 6SN7/12AU7 - I think that ship has mostly sailed. However trying different brands is still fun! Hence my interest in cheap types.
Something that irritates a tube vendor probably more than anything else is to call them up and ask for all sorts of brands on a relatively cheap tube. In the case of TubeDepot,
one of the most reputable tube vendors around, they already have notable tubes separately listed by specific mfrs. If you see a listing that says, "various brands,"
it already means that they're so cheap it makes no difference. If you are going to purchase something that inexpensive, ask to have a variety and order 6-12 at least. Or, start looking on ebay. Ebay is fine if the price is right and it's the tube brand that you want (or the construction is, see first reply above).
