Tube Quality

[Paul Philco322]

It must be tube weekend for me with my tube queries. What is the consensus on the quality of one tube manufacturer over another?
When you are digging around at a swap or shopping online is it worth trying to specify a brand for your purchase?

I know there were few manufacturers but many brands and have seen the charts with the manufacturers codes so you can tell who made a Silvertone or Emerson branded tube. So I guess the question is-- are RCA, Sylvania, and GE (the biggies) always your best bet?

I know that Philco bought up National Union and they made Philco tubes, and those were a quality tube as well.

I have seen some oddball names on tubes from the 50's and 60's some of which were made in Japan.

I would be interested in your opinions/experiences.

Thanks,
Paul

[codefox1]

All over the place. Many manufacturers made for each other up until the end of the tube era. When I was a kid, I worked in a jobber that sold Dumont Tubes, but I think less than half of the types were made by them. I do know that a lot were made by Telefunken and Mullard to cover replacements for the other side of the pond, for example. Yes, Japan and China made bunches of stuff too. China is still in the game, and quality is very good.

Millions upon millions of tubes were manufactured, and still there are millions sittling around in stashes, new used or of uncertain parentage.

You'll get 78 opinions of the possible 70 manufacturers. I love to see an original RCA or GE box with the same tube inside, or a JAN type, again appearing to be original. But then again, I've had wonderful stuff (Made in Holland) in old organ amps, including my C3 which I fire up once a week or so. 60 years old, still plays as new. Wish I could say the same.

So, tube trek. Many more mouths need to speak.

[TA Forbes]

Some varieties of tubes have interesting issues. The 6X5G short problem comes to mind, as does the issue of "noisy" 42 tubes and 36 tubes that test fine but wont function properly in an oscillator circuit.

[codefox1]

Yeep. 6X5G should be summarily forever disgraced, 6X5GT OK still lives in my ancient bridge which needs I think to be recapped and recarboned as it is getting a little flaky.

I tend to think there were only a few tube plants. I can recall the trip I tok to an unnamed pharmaceutical plant who stopped production from a famous name brand to a bargain brand for common aspirin and continued to extract powder and slam them into tablets. Same stuff. Now you know. Yeah, decades ago. Think things have changed?

[Paul Philco322]

I am aware Tungsol 6550 have a big following as a super amplifier tube,as Tungsol would say "tough as nails, sweet as Tupelo honey"

Paul

[Arran]

I'm always bugged by these threads where someone asks what the "Concensus" is about something or another, consensus is a $.50 cent word for public opinion. All of the big name manufacturers made decent tubes which all work fine if they test good. So an RCA, Sylvania, Tung Sol, National Union, KenRad, G.E, Westinghouse, Arcturus, Ratheon, Rogers, Canadian Marconi, etc, are all fine. Zenith did not make tubes themselves and neither did Philco, even though they had a stake in National Union, not sure about who made tubes for Sears or Western Auto for example.
The thing about Mullard tubes is such a farce, Mullard was the British division of Phillips which made identical tubes all over the world. This is more of the snake oil and fairy tales from the audiophool crowd, there is nothing wrong with them but they are no better then the Phillips branded tubes made in Eindhoven or the Valvo brand tubes made in Germany.
Regards
Arran

[Joe Rossi]

Paul,

Stay away from any tube that says "Shield" in green. These were factory rejects or used/abused tubes that were re-stamped. Sometimes they even had the wrong tube number stamped on them! They used to sell them at Olsons Electronics in the mid-west. Also, I've never had much luck with Silvertone. Otherwise I've found that, pretty much, all the name brands are reliable as well as Raytheon, Tungsol and JAN military. Heck, I have some tubes labeled Ford and Delco that perform great. What's more to the point is how reliable is the company or person you're buying them from. Joe

Next!

[Paul Philco322]

Thanks for the tip Joe. I think the Silvertone tend to vary, depending on maker. I have a radio that still has 2 original Silvertone tubes, from 1941. Though neither is the amp or rectifier. I have seen the Olsons ads in old mags.

Paul

[Don Lind]

Philco did make tubes at its Lansdale Tube plant.

[codefox1]

I think there are a few threads on tube makers now and then that are current. I doubt that there were more than 6 manufacturers at any one time in North America.

[Arran]

Quote:I think there are a few threads on tube makers now and then that are current. I doubt that there were more than 6 manufacturers at any one time in North America.

No there was more then six, there was at least four or five in Canada alone although some rebranded and resold the types they did not make. The main ones in Canada were, Rogers, Canadian Westinghouse, Canadian Marconi, RCA, and later C.G.E. C.G.E used to import many tubes before the war. I'm not sure if Sylvania had a tube plant in Canada prior to the war or not.
Regards
Arran

[TA Forbes]

I would not be suprised to find that there were certain tubes made by certain manufacturers that had problems.

This is an area that has little documentation. A place to document tubes by type, manufacture, and kind of problem would be interesting. By this I do not mean tubes that wore out, but rather noisy tubes, tubes with gas or shorts, etc....

I have noticed that 75 tubes often have a low/bad triode section but the diodes test fine. Never thought to note which brands had this problem.

Have also noted that 6H6 tubes often have one diode that is low/bad and one diode that is fine.

42 and 6J5s are often "noisy"

Also have had two 6F6s, one metal and one G, both were very noisy when hot.

There may have been certain makes/runs, etc, that had these problems. The info would have to be specific, like color of tube embossing, etched embossing, etc....

[Paul Philco322]

While many facets of radio manufacture started to get "value engineered" as time progressed it always surprised me that the tubes themselves seemed to be continually of very good quality. Even when many sets employed cheaper parts the tubes themselves held. I wonder why I think about these things!

Thanks to all for posting.

Paul

[codefox1]

This could go on for a while. I knew a couple of old timers (long before I bacame an old timer, way before,) that would storm out of the store if all I had was a Sylvania, no Dumont tube. Think they were both made together, with odds made in Europe and wherever a set of dyes were available. A vacuum on Mars is as good as one in China, or Jersey, or Kentucky or Moscow.

[TA Forbes]

Yep. And whether my ex-mother in law is riding a broom or a vacuum-cleaner, it's still a skyborne sign of the apocalypse.

Yep....