[mordy]

Hi 6SN7 thread folks!

I just replied to a PM asking for a comparison of the LinLai Elite-series 6SN7 vs the LinLai Grant Fidelity Special Edition 6SN7 globe. After realizing that I had just written a small essay on the two, I figured I should put it out there for anyone else who might be interested, as I found it very difficult to find info when I was considering buying a pair. I hope this is a good place to put this, but please feel free to let me know if it would fit better elsewhere. For reference, these impressions come from listening on a Woo Audio WA22 with Focal Clear, Sennheiser HD 600, Audeze LCD-X 2021, and Focal Celestee.

The good news is that they’re both very good and honestly pretty similar to one another. Both are quiet in terms of static / hum. They have great dynamics and are tonally rich, but quite detailed. As with all audiophile things, I am exaggerating the differences to try to help you contrast between 2 very high quality options.

The difference to me seems to be in frequency response. The GF SE globes seem slightly more ”U-shaped” - definitely not sucked out in the mids, but they strike me as bass-boosted and very slightly boosted on the very top end sparkle. They might both be a bit bass-boosted, but the globes a bit more so. Still, with the globes, because of that top end sparkle, they also come across as a bit more detailed / agile in the right situation. Interestingly, they seem to add a characteristic that I don’t have the right words for on cymbals, triangles, other metallic sounds. It seems like they make these more tonally dense, and not louder exactly, but exaggerated in a way that is musical and pleasant - kind of like a comic book drawing of the sounds in this metallic transient range using a thicker marker / pen. To be clear, the top end boost is high enough that it misses the sibilant range. I cannot stand sibilance, and I hear absolutely none with either of these sets of tubes. The globes are also the most microphonic tube I have ever dealt with. In this situation it probably doesn’t matter much - as we’re listening through headphones, but it if I touch them, or even tap or bump the housing of the amp, I hear a clearly audible ring. This doesn’t really show up when not bumping things on the amp, but just wanted to point out that quirk. One other thing to mention, many of the better modern production 6SN7s I have tried haven’t seemed to need much time to run in, they just sound how they sound from the beginning to my ear. With the globes, I thought they sounded really odd and just “off” at first. After about 10 hours of run-in, they seem to have evolved and stabilized into what I was describing above, so don’t be alarmed if you get them and think they sound bad at first.

The Elites are a bit more neutral. Again, maybe slightly bass-boosted, but very slightly so. They are still very clear and detailed. They remind me of the Psvane CV-181 TII, but with good quality control like they used to have. They’re a very highly competent and well-rounded performer. I don’t want my having less to say about them to imply that they are less special, but their biggest advantage is that they just give the 6SN7 goodness without adding any major coloration.

I think the choice is going to come down to synergy. For the WA22 I have a couple of pairs of 421a Western Electric power tubes, and those strike me as running the amp hard, with a bit of a bass boost of their own and generally aggressive and lush. It’s a great sound to my ear most of the time, though I do think it they can be prone to breakup on really complex, loud passages. For those I clearly prefer the Elite series, as the bass boost of the globes seems to cause a little bloating. I think this combo is an excellent choice for the classic rock and blues, but maybe not as much for more of the loudness-boosted modern rock and pop. As I type this, however, I have been rocking the 7236 power tubes, which are a bit more of a technical choice, similar (to my ear) to the stock 6080 with just a bit more authority in the bass, but a very neutral overall presentation with priority on speed and technicality. With them, I really like the slight extra bass boost of the globe and the additional musicality to the metallic sounds without getting in the way of the speed or making them piercing or harsh. The globes add a nice little something special in a couple of spots to what would otherwise be a neutral, but enjoyable experience.

So, to summarize, both sets are very good - no noise, quality seems to be on point. The globes have some unique sonic characteristics to my ear, and in some pairings seem magical, but in others might be a little less ideal - it will depend on your taste. With that being said, the difference is going to be subtle, and I don’t want to give the impression that the globes wouldn’t be good in all situations, they just have their own voice which must be taken into account in the overall synergy. The Elites are more of a neutral all-rounder, and if I were just going to have one set of 6SN7s but could roll the other tubes and headphones, I think it would be those. Overall, you can’t go wrong, but I hope this helps with making the decision!

I know a young man who took a summer job in a distillery that produced vodka. The vodka was bottled in eight different bottles one fancier than the next, and sold at eight different price points.
Problem was that all bottles contained the exact same vodka.

Every time I see a Chinese company selling a 6SN7 tube with different shapes, different print and packaging , and different prices, I think of that story.

In the history of tube making we do not find factories simultaneously producing several different variants of the same tube. The only difference were some tubes meeting more exact tolerances for military use (sometimes pulled separately from the production line) and long life tubes.

IMHO to take a tube and dress it up in different print and packaging and charge prices all over the map is a marketing ploy.

 

[jonathan c]

... to take a tube and dress it up in different print and packaging and charge prices all well over the mean is Bangybangian ...

FTFY...[Reg. TM; © bcowen: 2021.]

 

[Mr Trev]

I know a young man who took a summer job in a distillery that produced vodka. The vodka was bottled in eight different bottles one fancier than the next, and sold at eight different price points.
Problem was that all bottles contained the exact same vodka.

Every time I see a Chinese company selling a 6SN7 tube with different shapes, different print and packaging , and different prices, I think of that story.

In the history of tube making we do not find factories simultaneously producing several different variants of the same tube. The only difference were some tubes meeting more exact tolerances for military use (sometimes pulled separately from the production line) and long life tubes.

IMHO to take a tube and dress it up in different print and packaging and charge prices all over the map is a marketing ploy.

K. I gotta ask. When did the military really stop using tubes? I've seen military grade tubes from the 80s which I gotta think is well past the best before date regarding tubes - even by Warsaw Pact standards.
In high school, I was using Macs and personally had a C64 - soon to upgraded to an Amiga. I find it hard to wrap my head around the fact that the military hardware designed to wipe my existence out was still running on vacuum tubes

 

[S391]

K. I gotta ask. When did the military really stop using tubes? I've seen military grade tubes from the 80s which I gotta think is well past the best before date regarding tubes - even by Warsaw Pact standards.
In high school, I was using Macs and personally had a C64 - soon to upgraded to an Amiga. I find it hard to wrap my head around the fact that the military hardware designed to wipe my existence out was still running on vacuum tubes

It's totally possible that you had some vintage 1950's / 1960's weapon system still in use in the early 1980's. If so, some of those system could have still used tubes...

 

[leftside]

I know a young man who took a summer job in a distillery that produced vodka. The vodka was bottled in eight different bottles one fancier than the next, and sold at eight different price points.
Problem was that all bottles contained the exact same vodka.

Every time I see a Chinese company selling a 6SN7 tube with different shapes, different print and packaging , and different prices, I think of that story.

In the history of tube making we do not find factories simultaneously producing several different variants of the same tube. The only difference were some tubes meeting more exact tolerances for military use (sometimes pulled separately from the production line) and long life tubes.

IMHO to take a tube and dress it up in different print and packaging and charge prices all over the map is a marketing ploy.

Mullard did the same with their 10M tubes:
https://www.audioasylum.com/cgi/vt.mpl?f=tubes&m=286238

 

[Isaacc7]

K. I gotta ask. When did the military really stop using tubes? I've seen military grade tubes from the 80s which I gotta think is well past the best before date regarding tubes - even by Warsaw Pact standards.
In high school, I was using Macs and personally had a C64 - soon to upgraded to an Amiga. I find it hard to wrap my head around the fact that the military hardware designed to wipe my existence out was still running on vacuum tubes

The world of government contracting and procurement is Byzantine and not subject to usual ways of buying things. On top of that, tube manufacturing was not amenable to small quantity manufacturing. If it was determined that a few labs had equipment that used vacuum tubes it was probably less expensive to order replacement tubes than to replace the equipment. Or there could be different accounting rules for consumables vs. equipment purchases. Or the CRT displays and radar installations were deemed to be too costly/difficult to replace before their end of life. Manufacturers would impose minimum orders and/or there was an overestimate of what was needed and that’s how we end up with government surplus tubes.

 

[Tom-s]

Mullard did the same with their 10M tubes:
https://www.audioasylum.com/cgi/vt.mpl?f=tubes&m=286238

The famous Genalex Gold Lion vacuum tubes were the exact same thing. All Mullard production, with Mullard/Philips production codes for normal ECC81-82-83 etched on the tubes themselves. Collectors pay extremely high prices for these NOS Gold Lion tubes with B749 or other GEC code; thinking they are GEC.

Here's samples ECC81, 82 and 83 in "Gold Lion" versions. (Click on small pictures below post to see date codes on others. They are hard to read but say:
TK -> ECC81; GF -> ECC82; I6 -> ECC83



Same story with CCa tubes instead of E88CC tubes. People tend to think they are totally different tubes. Instead they are just the exact same tubes as all the rest from the production line. It maybe they were selected to a certain standard and printed CCa as sellers claim. It could also be they are reprinted normal E88CC. They share as an example the exact same (In this case Telefunkens) datasheet: https://frank.pocnet.net/sheets/128/e/E88CC.pdf

 

[bcowen]

K. I gotta ask. When did the military really stop using tubes? I've seen military grade tubes from the 80s which I gotta think is well past the best before date regarding tubes - even by Warsaw Pact standards.
In high school, I was using Macs and personally had a C64 - soon to upgraded to an Amiga. I find it hard to wrap my head around the fact that the military hardware designed to wipe my existence out was still running on vacuum tubes

It's possible Russia is still using tubes in their military equipment, and a lot of those are very low testing.

 

[g0ldl10n]

I am not sure where else to post this, but figured this is the best place to ask question in regards to the loctal version of the 6SL7, the 7F7.

Well, I recently just got a sleeve of 5 7F7 loctal tubes, with a base that I have never seen loctal tubes have before - extremely ruggerized with some sort of sleeve/housing around the bottom of the tube. With a flashlight, I can see that the glass extends all the way down to where you'd usually just see the metal wrapping at the bottom, with the pins, making the actual glass bottles the same height as the tall bottle 7N7 tubes.

I believe these were made by GE due to the sandblasted dots and the internals, however not only is the base very intriguing, instead of 'GE' being sandblasted on the glass, it is 'GT' along with a small frosted section of the glass which I presume was to write some notation on - I have only ever seen that on one other tube, the 7AK7, which was supposedly the first long life computer tube per Radio Museum. I wonder if these were some type of prototype design maybe? But look at this pictures, awesome

Edit: Actually, pertaining to the size of the glass bottle, compared to the tall bottle frankie 7N7 tubes, the glass envelope on these when lined up next to each other is about 1/2" taller than those - so, definitely the tallest glass envelope I have seen of any loctal tubes.

Has anyone ever come across this before? Any detailed information on what this exact design was made for? Have a look.

 

[LegionofDoom]

Does anyone have a more recent experience with the Sylvania 6sn7WGT?

While the early forum posts are insightful, I'd love to hear if anyone has experimented with it more recently.

I am considering it for a driver tube upgrade to my WA22 amp.

 

[Renexx]

Does anyone have a more recent experience with the Sylvania 6sn7WGT?

While the early forum posts are insightful, I'd love to hear if anyone has experimented with it more recently.

I am considering it for a driver tube upgrade to my WA22 amp.

I got a nice pair of 1956 Sylvania 6SN7WGTA. Love the etching in the glass. Sound is quite nice also. Maybe similar to a Raytheon 6sn7wgt. Quite warm with strong bass. Not bright or fatigue like others state at all. It's also not as refined as the earlier Slyvanias but still great. Be aware that later vintages of this tubes might not sound the same.

 

[leftside]

The famous Genalex Gold Lion vacuum tubes were the exact same thing. All Mullard production, with Mullard/Philips production codes for normal ECC81-82-83 etched on the tubes themselves. Collectors pay extremely high prices for these NOS Gold Lion tubes with B749 or other GEC code; thinking they are GEC.

Here's samples ECC81, 82 and 83 in "Gold Lion" versions. (Click on small pictures below post to see date codes on others. They are hard to read but say:
TK -> ECC81; GF -> ECC82; I6 -> ECC83



Same story with CCa tubes instead of E88CC tubes. People tend to think they are totally different tubes. Instead they are just the exact same tubes as all the rest from the production line. It maybe they were selected to a certain standard and printed CCa as sellers claim. It could also be they are reprinted normal E88CC. They share as an example the exact same (In this case Telefunkens) datasheet: https://frank.pocnet.net/sheets/128/e/E88CC.pdf

And what's even more confusing is that Genelex KT88 were indeed made my GEC (for export). GEC didn't want @bcowen confusing the GEC tubes with GE tubes.

 

[Isaacc7]

I am not sure where else to post this, but figured this is the best place to ask question in regards to the loctal version of the 6SL7, the 7F7.

Well, I recently just got a sleeve of 5 7F7 loctal tubes, with a base that I have never seen loctal tubes have before - extremely ruggerized with some sort of sleeve/housing around the bottom of the tube. With a flashlight, I can see that the glass extends all the way down to where you'd usually just see the metal wrapping at the bottom, with the pins, making the actual glass bottles the same height as the tall bottle 7N7 tubes.

I believe these were made by GE due to the sandblasted dots and the internals, however not only is the base very intriguing, instead of 'GE' being sandblasted on the glass, it is 'GT' along with a small frosted section of the glass which I presume was to write some notation on - I have only ever seen that on one other tube, the 7AK7, which was supposedly the first long life computer tube per Radio Museum. I wonder if these were some type of prototype design maybe? But look at this pictures, awesome

Edit: Actually, pertaining to the size of the glass bottle, compared to the tall bottle frankie 7N7 tubes, the glass envelope on these when lined up next to each other is about 1/2" taller than those - so, definitely the tallest glass envelope I have seen of any loctal tubes.

Has anyone ever come across this before? Any detailed information on what this exact design was made for? Have a look.

Those are some weird tubes. I’m guessing they were either a prototype like you said or else GE got a contract and made a batch. Are there any dates on them? If they were prototypes I would expect a fairly early date. A later one would make sense for the contract hypothesis.

 

[g0ldl10n]

Those are some weird tubes. I’m guessing they were either a prototype like you said or else GE got a contract and made a batch. Are there any dates on them? If they were prototypes I would expect a fairly early date. A later one would make sense for the contract hypothesis.

The only numbers printed on them (besides the dots - if anyone knows to decipher those, as I think those were actually placed/marked in a way that was used date) are 922-38, which they are all marked with. No other markings on them besides the branding and tube type - I don't think I have come across an EIA number of 922, and can't find anything searching online. 38, possibly 1938? The 7F7 on both Valve Museum and Radio Museum seem to both indicate the 7F7 was not formally introduced until 1940. However, I have some GE 6839 tubes which were not formally introduced until 1960 with manufacturing dates of 1959, but also marked with a later shipping date in 1960, so just like anything "new" that is released, the manufacturing dates (specially prototypes) are naturally going to be before the formal release date. But I am just guessing here. I have asked ask many people as I know, even some which I would consider extremely experienced (building tube amps since the 60s) and no one has ever seen anything like them before.

Edit: To add to this, I could have swore I did come across something awhile back that said something about the small frosted section you see there above 'GT' was typical of prototype tubes - but my memory may not be serving me correctly in this case.

If anyone knows how to use the dots to date, here are those close up.

 

[g0ldl10n]

The only numbers printed on them (besides the dots - if anyone knows to decipher those, as I think those were actually placed/marked in a way that was used date) are 922-38, which they are all marked with. No other markings on them besides the branding and tube type - I don't think I have come across an EIA number of 922, and can't find anything searching online. 38, possibly 1938? The 7F7 on both Valve Museum and Radio Museum seem to both indicate the 7F7 was not formally introduced until 1940. However, I have some GE 6839 tubes which were not formally introduced until 1960 with manufacturing dates of 1959, but also marked with a later shipping date in 1960, so just like anything "new" that is released, the manufacturing dates (specially prototypes) are naturally going to be before the formal release date. But I am just guessing here. I have asked ask many people as I know, even some which I would consider extremely experienced (building tube amps since the 60s) and no one has ever seen anything like them before.

Edit: To add to this, I could have swore I did come across something awhile back that said something about the small frosted section you see there above 'GT' was typical of prototype tubes - but my memory may not be serving me correctly in this case.




If anyone knows how to use the dots to date, here are those close up.

Now, I can't seem to find anymore pictures of the 7AK7 tube with the frosted section of glass like ones I have do. These 7AK7 tubes I have supposedly were from an estate of a "Space Race" NASA engineer. There are absolutely zero markings on these 7AK7 tubes, only classified on the sleeve itself - nothing on top and the only "marking" is the small frosted section just like these 7F7, and again, I could've swore I was researching what that was when I came across something that referred to prototype or experimental tubes prior to them going into production - but again, can't be sure - here is a picture.