NOS Tubes - Agony or Ecstasy -Part II - The Search


I thought I would do an update on my search for Tubes for my Don Sach's 6sn7 based Preamp.  The amp came with Shuguang we6sn7's.  Decent tubes once you get some good ones. About 3  out of 10 are bad.

So I started a search for some fine NOS tubes. Found the great reference threads on the Dehavilland and Head-HiFi sites as a starting point. I researched every possible seller except for Ebay, I won't buy anything on Ebay anymore.  I ended up buy tubes from a variety of sellers. Here are my experiences. Certainly not intending to critique any particular seller, just sharing my buying experiences.

I need matched pairs and wanted to mix brands including 50's RCAs, VT231's, 40/50's Sylvanias and Ken Rad.

Brent Jesse Recording equipment - ordered a pair of chrome top Sylvania's.  One tube dead on arrival. Sent them back and exchanged for a pair of older Sylvanias (bottom getter 2 rivet). He labeled them as "Bad Boys" but they are clearly not the 3 rivet version.  These tubes were so Microphonic they were completely unusable. One of them actually would feed back when tapped. Sent them back. I don't trust Brent's claims about testing so I will not order from him again.

Viva Tubes - Ok, so this seller has a bit of a reputation for hyperbole. In fact, all of his Sylvania tubes have "Bad Boy somewhere in the description, I guess for internet searches.  They are also mostly not true NOS but in his description "Tested NOS"? Whatever that means. He has a solid return policy for noise and miicrophonics so I went ahead and got a pair of Sylvania 2 rivet, bottom Getters, dated around 53. Tubes are great, pins needed cleaning but they sound great and have very low microphonics and no noise to speak of. So positive experience here.

TCtubes - Got a pair of 56 RCA GTB's just now. Zero microphonics, tubes look NOS, pins are clean. Burning them in but expect them to end up being keepers.  These guys are very responsive to emails, they just do not have a big inventory of 6sn7 but I'll buy from them in the future.

Vintage Tube Services - Andy has a great reputation and is 6 weeks behind on orders (maybe more like 8) So I ordered some Ken-Rads and am still waiting.  I have high hopes for Andy's tubes. Now that I have a basic stash it won't be so hard to wait a couple of months.

I also heard good things about Upscale but they did not have much in the way of NOS 6sn7's.  A couple of other recommended dealers did not have inventory.  There is one dealer on Etsy. However, he posted a photo of Sylvania's with hand painted logo so I shied away - he is very responsive to messages however.

At any rate - I hope that Andy finally gets those Ken Rad's shipped as I think they will be a great match to the Sylvania's - best of both worlds.  BTW, so far the descriptions of tonal qualities on the Dehavilland thread have been pretty right on the money.

drew.


drewh1
Is there a book out that has pictures of each tube with a description of what to look for to definitively say what you are buying?  If not, why?  I want to know when I pay a few hundred for 50's Mullards that I'm actually getting 50's Mullards and not being scammed because of my ignorance (which is epic).  And this is doubly true when you have no clue if they are actually new tubes and no way of testing them yourself.

It seems buying NOS tubes is a great way to blow a lot of money and never know what you actually bought.  Frankly they all look alike to me -- a tube with some plates inside.

Selling 1,000 counterfeit tubes at $100 each nets you $100,000 profit and probably no one will ever take the time to hunt you down for a couple of hundred dollar loss, especially if you are overseas. 

When I read that someone has come across this magic stash of NOS tubes that someone had stashed in their uncle's garage for 70 years I immediately think scam.  It's too easy. 

It's like buying fancy fish in your supermarket -- I read that most of the time even the stores don't know what they are buying.  A fillet looks like a fillet to most everyone, even the experts.
You should give Jim at valvesnmore.com a try.  I bought some very interesting 6SN7's from him as well as my favorite Sylvania 6SN7GTA.  Smaller, boutique operation run by an honest guy.  
If you want additional detail on identifying NOS valves, check out the Tube monger site. quite a bit of into.

https://www.tubemonger.com/
It’s a challenge and even though I’ve been using tube gear almost exclusively since the early ’70s, I don’t pretend knowledge about tubes in the kind of depth that would allow me to avoid fakes or bad examples. In fact, some are not fake but are not what they purport to be-- a tube I bought with made in Gr. Britain on the glass was actually an Amperex tube made for Mullard or Siemens in the U.S. back in the day when the companies would seek out manufacturing capacity to cover demand. Or so I learned.
I feel you on the source limitations too. Most are pulls not really new old stock. And some sources I used have pretty much dried up. I too have an order with Andy. Some of the common audio tubes are now harder to find b/c they are so popular; some less common, like the 6H30, which is in my line stage, are getting rare as early DR stocks depleted.(I didn’t like the sound of the modern tube in my unit, the DR had far more ambience). I don’t think there is an easy answer unless it is gear that is designed to sound good using a modern, readily available tube.
I only roll 1 tube on my amps, Lamm ML2- the 12ax7- easy to find pulls, not so easy to find truly new old stock (ribbed) and that is an "easy" tube--- there were a lot made.
Even rectifiers, which used to be common and cheap are now pricey for the desirable ones.
I also like to have a back up or two for each tube so I’m not in extremis; and these days, some tubes are spendy. At least if you get true NOS on small tubes, they should have long life. The problem with pulls is they may measure well, but can decline far sooner b/c they really aren’t "new"-- how many miles on them? Who knows....
+1 for Tubemonger - great photos of the classic NOS tubes, A big help for identification of tubes.  Tubemongerlib.com   

pinwa - thanks for the recommendation. I'll check out valvenmore.  

Just know, Sylvania and others manufactured tubes labeled for other companies. For instance, Hammond organs, Motorola, and others. I think these are fine tubes in most cases. So that does complicate matters. They do generally have the original makers ID number on them. These are listed on 
Regarding new tubes, for certain tube types, there are great new tubes out there.  300b for example:  EML, elrog, etc.  I think 2a3's have some great options as well.  6sn7s do not ):  
The KenRad VT231 is my favorite 6SN7, great tone with a meaty presentation

If you want to go deep into NOS territory you have to study and learn as to avoid nasty surprises.
Buying NOS and tube rolling without a cause is the best way to throw money but even today relatively easy to resell.
Something that we always forget is that modern gear is designed with new production tubes in mind. So if you want a better sound of your gear and not a different one try to locate the older made tubes but from same manufacturer.
When you hit the ones you want grab spares from same source asap.

G

Phillips was a Dutch conglomerate that owned many of the popular European tube manufacturers, Amperex, Mullard Siemens, Valvo, etc. Tubes from one manufacturer often would be labelled with the name of another manufacturer. To find out where and when the tube was actually made you have to look at the etched tube codes. Here is a listing of all those tube codes:

D:MyFilesWordPerfectPhiltitle.PDF (pocnet.net)

Etched tube codes can be hard or too faint to read, but if you want to know what you’re getting, you need to check these codes. There are probably people out there who can etch counterfeit tubes, but if you stay with reputable sellers, you should be OK.

If you decide to use the PHILIPS FACTORY VALVE CODES linked above, you only need to be concerned with the ’NEW CODE’ not the ’OLD CODE’ as illustrated on page 3.

NOS tubes are kind of a side line of high-end audio. I personally enjoyed learning about them and rolling them. If it doesn’t sound like fun to you, just go with new production tubes. That’s much cheaper and easier. Or, if you want to try NOS tubes, I recommend buying them from a reputable dealer and taking his advice. Learning about them and buying off ebay is very time consuming and higher risk.

There are reputable sellers on ebay with great tubes, but there are also crooks. No surprise there. You can find good European sellers on ebay, for example.

There are also tube manufacturers not owned by Phillips, like Telefunken, who use different methods of identifying their tubes. So it can get complicated.
drewh1, I didn’t mean to take your thread off topic. Looking forward to hearing your opinion on those 6SN7s.  Would you mind posting links to those threads you found helpful?
oops, links are screwed up, make sure to delete the extra http// 
"You can find good European sellers on ebay, for example."          I've purchased a number of excellent, NOS, European, small signal, nine pins, from this (highly dependable & conscientious, in my experience) guy:                                    https://www.ebay.com/str/tubesandradio
Without some sort of reference book I wouldn't know what the hell I was buying.  In coin and stamp collecting there are reference books that show each item, how to recognize it, what years it came out and was in circulation, etc. 

Some coins were printed with a "C" and later an "F" and you can look at what you own and check it to the reference book and be fairly confident with what you've purchased.

I would definitely need an analogue to these reference-type books for tubes if I were to ever go off the new-only path.  I looked online and cannot find anything that isn't related only to tube amplifier design or full of specs for each tube.  Nothing with a definite tube-identification slant. 

I've read through forum posts online and there are lots of people who know all this history but they haven't written it down yet that I can see.  I'd pay $100 for a reference book for tubes if it would save me $100 in purchases. 

I see online "Oh, you want an RCA from the 50's that was made either in this city or that city.  You can tell because the plates have 3 holes instead of 4 and because there is a vertical tab on the top plate.  But don't get it if it has dark silver plates because those were made by another company.  Even better is if the getter has 3 sides instead of 4 because those were used in the Army and have better microphonics.  Don't buy it unless it tests 1000 or more on transconductance and never use it unless it's been matched to within 10% or you will have a base plate voltage that is too low and your bias will actually have to bet reset 20% lower or you'll overdrive the tube.  Now even better still are the JAN versions that are marked "7189A" or "7189AB" because the vacuum of these was drawn to a much higher pressure and the tubes themselves are twice as thick, but never ever buy them if..."   

How the crap am I to know any of this?  How do I even know if the guy I'm talking to about tubes is full of it or not?  "Well, it's easy, you just buy this here book and read it from cover to cover!"  OK, where is it?  I'll buy it.
Sorry if I hijacked this thread.  My apologies.
shawn, It doesn’t exist.

You should call a reputable dealer, tell him what your system consists of, what sound you are hearing now, what changes you would like to hear, and how much you want to spend. Start with one pair of tubes and see how it works out, then go from there. A good tube seller has many years of experience, and a lot of testing gear, so there’s no good reason for you to try to duplicate all that unless you really want to spend a lot of time getting into tubes. A good seller will accept returns on tubes with problems, so ask what his return policy is.


drewh1, Thanks for the links.
I've always gotten nice tubes, well packed from  Langrex Vintage Electronics

LANGREX | eBay Stores

They're in England.  They have 99.8% positive feedback on 66,573 transactions.
@tomyc6, nice score but I bought from them some years ago and they have sent me end of life Mullards, i believe they have become better by now. Few sellers now on ebay are trustworthy.
Most sell on GM or plate readings based on book specs but that has nothing to do with tube life or condition as no one knows what were the initial reading of that tube. That for used or the misleadingly term nos.
Best thing is to know beforehand the tube you are looking for as to avoid trial and error.


G
shawn - the information is out there, you just have to dig for it. AND, you only need to be knowledgeable about one or two types of tubes.

Call Andy at VTS, he is honest and won't try to sell you anything you don't need.
http://vintagetubeservices.com/contact-andy/


Thanks for everyone's help.  I'm learning.
@tomyc6, nice score but I bought from them some years ago and they have sent me end of life Mullards, i believe they have become better by now. Few sellers now on ebay are trustworthy.

Wow, @petg60, Sorry to hear that. All I’ve ever gotten from them are brand new NOS tubes, and I’ve tested them and they’ve tested new too.

Were your Mullards advertised as NOS?
Just a quick report on my impressions of these tubes.  My Don Sachs preamp uses 2 pairs of 6sn7's, one in buffer, the other driver.  

The Sylvania's have a lot of sparkle, In the driver position, they are great on detail but female vocals a bit grainy, maybe too much of a good thing. A bit lean on bass.  If your system tends to the dark side, these would be a great match.

The best combination seems to be the RCA's in driver with Sylvania's in buffer.  Great details and separation of instruments, vocals are smooth and sweet, bass is very nice. very holographic, the magic I have been looking for.  Seems to be a good synergy.

Either combination is more enjoyable than the Shuguang's. Although they had a balanced frequency response, not much detail or depth with them.

Again, can't wait to try the Ken Rad's in combination with either of these.
@tomcy6, 
unfortunately yes.
I enjoyed the tubes for 10hours though.

G


Yeah, drewh1, the right tubes can add that little bit of magic.

petg60, you should have been able to return those tubes for new ones.
I thought the Sylvania JAN 231's I tried were addictively transparent but recessed in the bass.  I chose a fuller sounding tube that I like better, but no longer listen for such exrended periods.  Strange how I rated one tube as quantifiably better but was drawn to the Sylvania's musically.
I thought the Sylvania JAN 231's I tried were addictively transparent but recessed in the bass. I chose a fuller sounding tube that I like better, but no longer listen for such exrended periods. Strange how I rated one tube as quantifiably better but was drawn to the Sylvania's musically.
I have to agree with that for the various Sylvania's I have  tried.  I think that is why I like to mix of Sylvania and RCA. I still seem to get some of that sparkle and transparency with a fuller bass and midrange.