[mordy]

2399 is not a different kind of 5998. It is a truncated version of IBM's inventory number for the 5998.

IBM purchased tons of 5998 for use in their early computers. And in fact, IBM purchased so many of them, that Chatham / Tung Sol often put IBM's part number on these tubes: 3002399, or 2399 for short. Otherwise, they are just a 5998. Nothing special.

If they sound different, it is likely due to different dates of manufacture.

The poor guy in the picture has to look for the bad tube among 19,000 tubes...

 

[No Deal]

When paired with another similar tube, how much does the two tubes vintage matter if they both test good?

 

[mordy]

When paired with another similar tube, how much does the two tubes vintage matter if they both test good?

In many amps the matching of the tubes doesn't matter much. You may not be able to hear the difference between a pair of the same tubes where one measures NOS and the other other barely good.

When you say similar tube, I don't know exactly what you mean. There are times when two different, but similar tubes, may complement each other in sound (ECC31/FDD20 as an example), and there are times where the same production tube from different years may sound different enough to be noticeable.

 

[No Deal]

In many amps the matching of the tubes doesn't matter much. You may not be able to hear the difference between a pair of the same tubes where one measures NOS and the other other barely good.

When you say similar tube, I don't know exactly what you mean. There are times when two different, but similar tubes, may complement each other in sound (ECC31/FDD20 as an example), and there are times where the same production tube from different years may sound different enough to be noticeable.

Both tubes would be 5998s. I am trying to make a pair. I own one (Tung Sol) now and I have not seen another that is the same year or version as the one that I have. Wasn't certain if it matters.

 

[mordy]

Both tubes would be 5998s. I am trying to make a pair. I own one (Tung Sol) now and I have not seen another that is the same year or version as the one that I have. Wasn't certain if it matters.

I don't think it makes much of a difference. I myself have an IBM and a Tung Sol 5998 pair and as long as I don't look at the tubes it does not bother me LOL!
The two tubes sound pretty much the same, but I can understand people that want that the tubes should look exactly the same.

 

[bpiotrow13]

If Chatham sold tubes branded RCA it seems to me that you should be able to pick up RCA branded Chathams for less than the going rate for Chathams. How can I identify them?

Rca branded Chathams are very rare. Except for mine i have seen them only once...

 

[bpiotrow13]

2399 is not a different kind of 5998. It is a truncated version of IBM's inventory number for the 5998.

IBM purchased tons of 5998 for use in their early computers. And in fact, IBM purchased so many of them, that Chatham / Tung Sol often put IBM's part number on these tubes: 3002399, or 2399 for short. Otherwise, they are just a 5998. Nothing special.

If they sound different, it is likely due to different dates of manufacture.

Thanks, very helpful.

 

[Flisker]

as long as I don't look at the tubes it does not bother me LOL!

Exactly

I would go crazy, trying to listen to different tubes. Different date codes, that I can manage, but different construction or different branding would be big struggle

 

[mordy]

Exactly

I would go crazy, trying to listen to different tubes. Different date codes, that I can manage, but different construction or different branding would be big struggle

I know the feeling, but if the tubes look different but sound very good together, it is OK with me. Certain early tubes, even the same brand and same designation, may come in many different variations. For me, part of the challenge of acquiring tubes is to get them at a good price. Often this means buying odd lots and sometimes singles. I end up with a bunch of tubes that don't have exact pairs, and I try to match two of the same type and brand and the same or similar construction. Often they sound almost the same or the same, even if they have different construction.
I have also found that when it comes to older tubes many times two tubes from the same year and the same designation may be different in size, one being taller or shorter than the other. Recently I bought four Ken-Rad 6J5GT (labeled BRIMAR) from the 1940's and every single tube was a different size than the other...- I had to laugh seeing it...
PS: I once saw in a shoe store a mismatched pair on sale (7 and 7 1/2). The sign said "Near Pair."
Well, some of the tube combinations I use and like are "near pairs."

 

[No Deal]

Exactly

I would go crazy, trying to listen to different tubes. Different date codes, that I can manage, but different construction or different branding would be big struggle

If I can acquire the second Tung Sol it would be my third and last pair. I have been trying to find one that is the same age as the one that I have. I am ready to give up. In the meantime I have found the 6AS7g to be a very nice tube.

 

[Thaddy]

If I can acquire the second Tung Sol it would be my third and last pair. I have been trying to find one that is the same age as the one that I have. I am ready to give up. In the meantime I have found the 6AS7g to be a very nice tube.

I'll send you a PM.

 

[mordy]

I'll send you a PM.

If I can acquire the second Tung Sol it would be my third and last pair. I have been trying to find one that is the same age as the one that I have. I am ready to give up. In the meantime I have found the 6AS7g to be a very nice tube.

Don't give up! Tubes were made in the millions, and if you are patient, they will surface and come up for sale. It may take a while, but they will come up...

 

[exchez]

I've seen GEC/MWT 6AS7G tubes with a non-curved brown base and cup getters have either a Z or a 4 in the lower right corner of the A1834 box. I believe the Z stands for the Hammersmith factory, but does anyone know what the 4 stands for?

 

[Monsterzero]

I believe the Z stands for the Hammersmith

Did somebody say "Hammersmith"?!?
One of the best live albums ever!

 

[exchez]

Did somebody say "Hammersmith"?!?
One of the best live albums ever!

Once I get a matching A1834 it will be the first thing I listen to