KT77: truly NOS NIB?

electroking

electroking

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This ebay auction (number 330377365391) offers a quad of supposedly
New Old Stock New In Box British made tubes. I found them because
I often search the Canadian Marconi Company name on ebay.

The funny thing is that the two letter date codes on the box (PS) and
on the tube (QD) don't match (this is what I read for the second tube
from the left).

I would assume that the tubes in these four boxes are pulls that
were replaced a long time ago by the original contents of the boxes.
 
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The 1st, 3rd, & 4th appear to used to me. The darker brown, almost black at the top of the base fading to lighter brown towards the pins is usually caused from heat during use. It could be an artifact of the picture and they are actually an even color but that some are marked Sylvania and another Westinghouse while sitting in Marconi boxes is just odd. Or, the Marconi's went into an amplifier and these were removed from it.

:dunno:
 
Not NOS. The half darkened basses are consistant through the photos. Not an artifact of photography. The brown basses on my tubes change after 50 or so hours.
 
Still a nice looking quad at a good price right now. I think I have a little over 800 in my used quad.
 
soundmotor said:
The 1st, 3rd, & 4th appear to used to me. The darker brown, almost black at the top of the base fading to lighter brown towards the pins is usually caused from heat during use. It could be an artifact of the picture and they are actually an even color but that some are marked Sylvania and another Westinghouse while sitting in Marconi boxes is just odd. Or, the Marconi's went into an amplifier and these were removed from it.

:dunno:
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I sent him a question regarding these things. I think you are spot on.:yes:
 
The tubes are NOS. Culled from a large collection of KT77s sourced for the Canadian market and hand picked for the best match.

The tubes came from a dear friend who pretty much wrote the book on GEC/Mullard code deciphering in the early 1990s. One of the few individuals who can actually tell used from NOS.

He had kept the quad all these years because he planned on retiring on a 8B with a premium set of KT77s. A little change of plans and here they are.

They are definitely NOS. As they don't have any burn markings of any sort. The tube bases on 1968 production can look darker, as this is a function of the bakelite material used.

It is also useful to point out that GEC burned-in every KT77 tube at the factory for several hours. Like any other reputable manufacturer of the day would do.
 
I find it curious that the only tube which is shown in close up is the one with the lightest base. :scratch2:

It's likely that what soundmotor said occurred. Somehow this mix of Sylvania and Westinghouse labeled GEC KT77s ended up in the Marconi boxes. When Marconi sourced KT77s it would have been from GEC itself, why buy through a second party, especially two second parties, and pay more, makes no sense. Also any Marconi relabeled tubes I have are clearly labeled as such.

These may well test as NOS but they should be sold as ANOS, not NOS.

This is a definition issue. I recently purchased some tubes that were being sold as NOS but they had been removed from 'unused military equipment'. As far as I'm concerned once a tube has been installed it is used.

A lot of people who bought new tubes to put into their gear would remove the old ones and stick them in the new boxes. I suspect that this is what occurred with this quad. Thing is the person may well have replaced the tubes unnecessarily and the tubes coming out may well have been fine. Of course the price of these back then was a lot less so replacing tubes this way was a common practice to trouble shoot problems as the majority of people didn't have tube testers and the drug store testers wouldn't test for mutual conductance.

In this case the seller should be saying: These tubes test as new old stock but since I cannot be certain that they are NOS, because of the fact that the tubes do not match the boxes, they are being sold ANOS.

Cheers

Lar
 
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I think what happened was that during the selection process not only the best matching tubes were chosen but the best boxes as well. Turned out to be the Marconi ones. It is possible to have water damage on a box, and the tube still be NOS, never used. Happens all the time.

The tubes are definitely new. They have never seen use in an amplifier or other electronic device.
 
Cool, the ones I have are amazing in the souped up ST 70.:music: I don't run them much though, just special occasions.:smoke:
 
I worked close on 20 years for GEC Marconi.

I have four GEC KT77 and they do look like those in the picture (different boxes of course).

I run JJ KT77 and have found the sound same as the GEC, but they are cheap and easily replaceable.

(Radford STA25 III)
 
Radfordman said:
I worked close on 20 years for GEC Marconi.

I have four GEC KT77 and they do look like those in the picture (different boxes of course).

I run JJ KT77 and have found the sound same as the GEC, but they are cheap and easily replaceable.

(Radford STA25 III)
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Good to know you worked for GEC. Great company back in the day.
Didn't the JJ's have some QC issues when they first came out? I hope they are have been corrected by now.

I tried a set of Russian Gold Lion reissues a year ago. Sounded nice, but a tad darker than my 1997 SED/Svetlanas. I kept the SEDs.
 
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crooner said:
Good to know you worked for GEC. Great company back in the day.
Didn't the JJ's have some QC issues when they first came out? I hope they are have been corrected by now.

I tried a set of Russian Gold Lion reissues a year ago. Sounded nice, but a tad darker than my 1997 SED/Svetlanas.
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Yes, I read that there were quality issues early on. I bought 10 JJ KT77 about 18 months ago, all fine.
 
Radfordman said:
Yes, I read that there were quality issues early on. I bought 10 JJ KT77 about 18 months ago, all fine.
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That's cool, because I believe the folks at JJ actually dissected a GEC KT77 to reverse engineer it. Somebody had to donate one to science so to speak!
 
crooner said:
I think what happened was that during the selection process not only the best matching tubes were chosen but the best boxes as well. Turned out to be the Marconi ones. It is possible to have water damage on a box, and the tube still be NOS, never used. Happens all the time.

The tubes are definitely new. They have never seen use in an amplifier or other electronic device.
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The ad shouldn't state NOS NIB QUAD GEC KT77 TUBES then.

NIB means new in (original) box.

Cheers

Lar
 
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