Have a few questions. At the risk of reopening a sensitive topic about a recent tube purchase, I am only doing this to deepen my understanding of tubes.
I recently purchased a pair of 6AS7G tubes. The seller on ebay said they were Tung-sol tubes. One was branded Tung-sol Chatham and the other National. The seller said the manufacturer code was the same on both tubes.
On looking at them, the one branded Tung-sol has a number of 322DN3 and the other tube branded National has the number 3226305. Can I take it that the 322 portion of the number is the Tung-sol manufacturer code? It is after that 322 which is different. I'm including photos of the tubes and listing physical differences they have.
Don't know what the part is called, but you can see the contrast of the copper tube going up the middle of the tube. Also, please note the silvery stuff at the bottom of the tube. This is the Tung-sol Chatham tube and it has that copper part and the shiny stuff at the bottom. The other tube, branded National does not use copper for this part, and there is no silvery stuff at the bottom as you can see.
The other differences are at the top of the tube. The one branded Tung-sol Chatham is clear and the one branded National has silvery stuff up there.
So my questions are:
- Does the copper have any sonic value over the non-copper?
- What does the silvery stuff at the bottom of the tube do and does its presence/absence have any sonic consequences?
- What does the silvery stuff at the top of the tube do, and like #2 above, does its presence/absence have any sonic consequences?
From a vendor who is looking at tubes from the perspective of manufacturer codes, it would make sense to me that they would see them as the same. However from a music listener perspective, are they the same? From the perspective of listening, the amp sounds better with them in, so I moved in the right direction which is good. Would I want to keep my eye out for another tube that is more like the one with the copper parts? I am very new to tube rolling, and have a lot to learn, so I am interested in the different perspectives out there regarding the match of tubes.
One last question. I am breaking in a different pair of power tubes, this time what look like a "matched" pair of RCA 6AS7G's. Everyone once in a while I am hearing a very quick pop in my left earphone that is not a result of the music or line-noise. I heard one on the right side. I have never heard tubes pop like that. Should I return these tubes?
Thanks.