There were never very many tube "manufactering plants". Rebranded tubes are very common.
14 responses Add your response
Its only a 30 minute drive or so....and when you walk in the store/warehouse, all you see are tubes. Tubes from all different sizes and some I believe he is collecting as they are in glass cases.
Only issue ( if you want to call it that ) is that he starts talking specs, numbers, history of each tube and then he loses me....but its still cool to go there.
If they test the same they should be fine, as a general matter, and it is quite possible they are rebranded as Mofimadness points out. Not sure if you really need a matched pair for the preamp, what brand pre is it? Just because it uses two tubes doesn't mean that they are one for the gain on each channel.
After thinking about this some more,I felt I needed to add something.As long as the tubes are of the same construction and spec test within 2 or 3 percent of each other,I don't think they have to be labled the same to be called "matched" unless they are something special,like original Telefunkens,Amperex Bugle Boys,etc.A lot of people don't realize that tube mfgrs sold to hundreds of clients that used their own labeling such as Baldwin,McIntosh,etc.The bottom line is still "I have listened to them and notice no difference".This is strictly my opinion,others have a right to disagree.
I doubt that the two tubes are rebranded versions of each other, or of tubes from any other manufacturer, apart from the possibility that the Amperex may have been made by Philips, which acquired Amperex in the 1950's. RCA and the Amperex brand (both before and after its acquisition by Philips) were both tube oem's (original equipment manufacturers).
They both made quality tubes, as well. If the Amperex has a "bugle boy" logo on it, it is particularly well regarded (and valuable).
As the others have said, if the seller selected tubes that measure close to each other I wouldn't worry about it any further. And RCprince makes a good point too, that depending on the circuit design it's possible that there is no need for them to match, anyway.
Wow! If Jim Cross, past president and present board chairman of the Tube Collectors Association, says they are matched, they are matched.
Lucky you, being near his store and its 250,000 tubes, and having his expertise conveniently available as well!