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Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?

71.17.118.57
Posted on November 4, 2009 at 09:13:54
diamondsouled
Audiophile

Posts: 608
Location: The Great White North
Joined: May 2, 2007



Just picked up these nice 5932 tubes as well as a quad of Bendix 5992s for a good deal from the same seller.

Thing is that they were both listed and described as NOS.

This is what the seller said when I asked him about it:

"Hi Because they are source from unused equipment. Many tubes sold to the government are never in boxes

Also by the readings and the internal condition of the tube."

Don't get me wrong these are beautiful looking tubes that do test as NOS, look like NOS: clean pins, clean bases, clear printing, great getter flash, but having been installed in equipment, even if that equipment has never been turned on do they really meet the definition of NOS?

Cheers

Larry Rowe
Thanks for all the responses! ;^), posted on November 5, 2009 at 08:53:58
diamondsouled
Audiophile

Posts: 608
Location: The Great White North
Joined: May 2, 2007
 They've confirmed for me that the term NOS has to be taken with a big grain of salt no matter if the tube in question is still in the box or from: 'bulk packs' or: 'unused equipment'.

I'm still coming across genuine NOS audio tubes myself so I know that they are still out there, how many of them make it to eBay I'm not sure but there are some to be sure.

I guess the thing that I look for in a seller is openness and honesty. I like it when I read: "this tube comes in an original box but I cannot be sure it is NOS so bid accordingly."

When going through an elderly gentleman's tube stock from his TV repair shop here in town in the last month or so there were lots of NOS NIB tubes but when going through the boxes to check them I did come across a few used tubes.

Only some 20 NOS audio tubes out of several hundred NOS radio and TV tubes though.

Cheers

Lar

RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 5, 2009 at 06:10:05
Tom Bavis
Audiophile

Posts: 397
Location: Upstate NY
Joined: May 25, 2007
 Probably better than "NOS". Selected military grade parts with no or minimal hours, likely from the same production lot.

Consider that "NOS" tubes, even at the best dealers have mostly unknown history. With the exception of a cellophane sealed Telefunkens and some stapled military boxes, what's left for NOS?

> Mixed date codes from various sources - except for manufacturers, depots and distributors, most tube stocks were spares with a few each of many numbers.

> Tubes near the upper and lower limits which couldn't be matched, or weren't used if a better one was on hand.

> Used tubes that were returned to their boxes after routine replacement (they were still good, after all...)

> Late production military spares from long after the period when quality control was at its best. Also, by the '70s, tubes came from wherever they could be found - often Eastern Europe.

The trouble with NOS is......, posted on November 5, 2009 at 00:23:55
Frihed89
Audiophile

Posts: 8435
Location: Copenhagen
Joined: March 21, 2005
 that the term has been rendered increasingly meaningless, both in terms of widening the definition and the use of the term by tube sellers.

I now look for used tubes -- "pulls" -- that test good and are not unduly microphonic. I have found sources who don't lie about the "status" of a tube or the test results and whose prices are reasonable. So, what do you pay for a pair of true NOS (unused) Bugle Boy 6DJ8s? How many Bugle Boys that test 80-90% of the new value would it take to replace these? I can buy 10 pairs of these used tubes for around the same price.
"What did the Romans ever do for us?"
RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 16:29:24
Neff
 I say yes to NOS, but add unused equipment pulls to remove any possible confusion. Some also collect tube boxes & pulls do not have a box.

RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 15:15:04
PakProtector
Audiophile

Posts: 9949
Joined: May 14, 2002
 hey-Hey!!!,
I got some 6AR6's from torpedo guidance amps. I am pretty sure that the torpedoes were unused...:) I don't think that the install and potential testing put any apreciable wear on them.
cheers,
Douglas

Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 09:31:43
Michael Samra
Dealer

Posts: 13111
Location: saginaw michigan
Joined: January 30, 2005
Contributor
  Since: June 24, 2005
 Larry
Yes,they are classified as bulk new old stock but they aren't new in box.You can tell those are new and even if they were slightly used,the price you paid the guy was so minimal it wouldn't matter.
Lar, the plate structure in those tubes look like a 350b and I would try them in your quad amps.They will be fantastic.
If the power supply waveform isn't pretty,neither is the sound in most cases.
RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 10:36:05
astralnavigator
Audiophile

Posts: 570
Location: North York, Ontario
Joined: June 28, 2009
 No, they are nothing at all like a 350B.

The 5932 is a tube that is not terribly well known, it is really a very ruggedized 6L6GB as it does not have the voltage ratings of a 6L6GC, and came in three versions. The ones in the pictures are the dual plate version and that is a very nice sounding tube. It also came in a single plate version that is not so great sounding and a version that had a large hole in the plate which is terrible sounding.

A word of caution, though - the 5932 has a very large base and amps with close sockets may be challenged, and the 5932 generates a lot of heat.

RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 12:59:57
JSTRM
Dealer

Posts: 176
Location: Montana
Joined: March 7, 2003
 There is also another version. Very rare. TungSol had their version for gov needs. Glass/base same on all variations. TS took their 5881 and surrounded it with the base/envelope. Very cool tube, used in Naval and other radar systems.
jstrm
RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 10:05:45
FenderLover
Audiophile

Posts: 3309
Joined: July 31, 2007
Contributor
  Since: May 17, 2009
 Yeah, many NOS tubes are pulled from unused equipment & test well. One thing I've noticed with 6DJ8-type pulled from unused scope, is they maybe noisy. As audio noise may not be important for their function in other equipment. So it's good to have the tube tested for noise as well as strength.

The Sylvania 5932 is a good tube. I find they sound the best if you bias them like 6L6GB or 5881. Keep the anode plate voltage around 350-360 VDC and plate watt dissipation, at idle, of around 15-18 watts per tube. Fine tune to tone.

Same with the 5992. Don't put them in amps that run +400 VDC on the plates. Keep the idle bias below 10 watts dissipation. They do not like the settings of early Fender amps which really pushed the 6V6GT's.

Good luck with those tubes!

RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 09:56:29
diamondsouled
Audiophile

Posts: 608
Location: The Great White North
Joined: May 2, 2007
 Hi Mikey,

Yup I know about the bulk pack thing but he's including in his definition of NOS tubes that have been installed in 'unused' equipment.

When I get my Quad IIs unpacked I plan on trying them out, ;^).

Just finished rebuilding that pair of Electrohome 6V6 slave amps I picked up recently. Boy they sound great now! Used one of the CDE polys after the rectifier.

Cheers

Lar
RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 12:38:02
Palustris
Audiophile

Posts: 251
Location: Cape Cod
Joined: September 12, 2008
 I don't see the point in getting into semantics, but just for the record if the equipment is "unused" then by definition it is new.

RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 13:00:16
diamondsouled
Audiophile

Posts: 608
Location: The Great White North
Joined: May 2, 2007
 The problem as I see it is that the term: 'unused' is sort of a gray area. To one person 'unused' may mean that it was plugged in and tested for a while but then taken out of service. The person taking the tubes out of the gear has to take the person they got the 'unused' equipment from at their word so the 'unused' term is probably not first hand but second or third hand information. In other words it's impossible to confirm.

Cheers

Lar

RE: Does a tube that looks and tests NOS but comes from unused gear qualify as NOS?, posted on November 4, 2009 at 15:59:24
Ty_Bower
Audiophile

Posts: 195
Location: Newark, DE
Joined: June 9, 2007
 Quote: "The problem as I see it is that the term: 'unused' is sort of a gray area."

Yes, it's rather a bit like zombies and vampires - i.e., they're "undead". What exactly is that, anyway?
Really, is this a problem?, posted on November 4, 2009 at 14:41:20
andy evans
Audiophile

Posts: 997
Joined: October 20, 2000
 I don't really "get" this thread at all. A tube is a tube is a tube. If it looks like new, tests like new and smells like new, why not consider it a new tube? After all, it's indistinguishable from new.

Just reflect on the fact that you can get much worse condition tubes in new never-been-opened boxes.

If you've got new testing tubes, frankly that's all you need to know.

andy
Yes, it can be..., posted on November 5, 2009 at 05:29:19
astralnavigator
Audiophile

Posts: 570
Location: North York, Ontario
Joined: June 28, 2009
 A tube is not a tube, and if it tests new, it's not necessarily new at all.

A tube's useful life is not linear. It will test as new during most of it's useful life, and then when it starts to decline, will do so very rapidly.

So unfortunately there is a prtoblem here. Far too many tubes that test as new are sold as NOS when, in fact, they are very heavily used and have relatively little useful life left in them.

That, in itself, may not be a problem if they are priced low. But they are almost always not, being sold on auctions that prey on the obsessiveness of audiophiles who, given that true NOS is now quite rare and given the scarcity of desireable tubes, end up parting with far too much money for what they actually receive in longevity of (supposed) audio bliss.

I have had new testing tubes that have cathodes stripped from use - in many cases, the cathodes are gonzo long before output declines - and I have had tubes that test new for a very short time then drop off the cliff.

In terms of pulls and supposed bulk stock, it has long been a practice of an all too large number of tube sellers - usually the selling out of my basement type - to pass off tubes that look, test and smell like new as "from bulk pack", "NOS in white box" or "NOS from unused equipment". In most cases, what they have is a tube that looks, tastes and smells like new that they are trying to elevate the price of by giving the buyers a false sense of security.

The simple reality is that, aside from a small number of professional dealers (and even those have a fair number of suspect tubes) there has been very little NOS of desireable audio tube types for a long time, and pretty much everthing - especially virtually everything on Ebay - is highly suspect at this stage.

RE: Yes, it can be..., posted on November 7, 2009 at 08:32:55
Jim McShane
Dealer

Posts: 3405
Location: Chicago
Joined: January 13, 2003
Contributor
  Since: April 11, 2002
 Be careful here... I think you are painting with a very broad brush.

For example, you wrote:

"In terms of pulls and supposed bulk stock, it has long been a practice of an all too large number of tube sellers - usually the selling out of my basement type - to pass off tubes that look, test and smell like new as "from bulk pack", "NOS in white box" or "NOS from unused equipment". In most cases, what they have is a tube that looks, tastes and smells like new that they are trying to elevate the price of by giving the buyers a false sense of security.

This could EASILY lead someone to believe that unless a tube comes with a box they deem to be original that the tube is a fraud. Not so! Do you want me to take some pictures of the 12AT7 bulk stock RFTs I have? Or the EZ81s? Or the 6GK5 Hitachis? I can't take a pic of the bulk pack Ei KT-90s I had 500 of a few years back, they're gone. How about the older tubes where the boxes have simply disintegrated or had rodent damage?

You can say that an unscrupulous vendor could take advantage of the fact that some tubes will not come packed in an original retail box - but I think that's all you can say. Believe me, your post will require me to spend HOURS assuring people that they are getting the product they paid for.

"I have had new testing tubes that have cathodes stripped from use - in many cases, the cathodes are gonzo long before output declines"

Please explain how you made this determination... what tests did you run? How did you determine the decrease in cathode activity was from stripping (which BTW RARELY occurs at typical audio gear voltages)? How is it that a tube with a depleted cathode ("the cathodes are gonzo") is able to operate normally - what caused the later decline?

"The simple reality is that, aside from a small number of professional dealers (and even those have a fair number of suspect tubes)..."

This is a pretty strong accusation. Could you please tell me which tubes I've sent out have been suspect - and how you made that determination?

I don't do that kind of stuff, I never did that kind of stuff - so I don't want to be painted with that same broad brush.

I'm not trying to pick a fight, but I will always respond to this sort of post the way I did. Some of us out here do a damn good job of offering quality and value in the products we send out. And I for one am very sensitive about being caught up in sweeping generalizations.
Useful post! (nt), posted on November 5, 2009 at 11:15:13
andy evans
Audiophile

Posts: 997
Joined: October 20, 2000
 .

Not really ;^), posted on November 4, 2009 at 19:37:14
diamondsouled
Audiophile

Posts: 608
Location: The Great White North
Joined: May 2, 2007
 For me NOS is New Old Stock with an emphasis on the stock part. Once it's been taken out of stock and installed it's no longer in stock so it's no longer NOS to my mind. Still like you say the important thing is how the tube tests and looks.

No more of a guarantee with buying a tube that's in a box that it is truly NOS and has never been used.

Cheers

Lar
" NOS ", posted on November 4, 2009 at 14:14:47
FenderLover
Audiophile

Posts: 3309
Joined: July 31, 2007
Contributor
  Since: May 17, 2009
 Also, problem is just becuase tube is truly NOS, doesn't mean it's going to be the best sounding tube of the lot. Or last the longest. These days some NOS aren't too good. Like the leftovers of all the NOS tubes which have already been sold. Just my opinion.

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