Why the internet disinformation campaign about 5881/6L6?

Dacious

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Who makes the tubes that Mesa test/brand? I understand they are from China - does that imply Shuguang?

The STRs are Chinese I think - Ruby sells them as STRs too they have C in the model name. The JJs are branded Y for Yugoslavia. The Sovs are branded R.

Mesa burns them in and matches them.
 

dlew919

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In my observation there are two internets: the expert internet - places like here, gretsch talk, mandolin cafe, a Subaru forum I lurk, where the information is considered, smart and if wrong usually inadvertent and quickly corrected.

Then there’s the angry internet. Information is based on nothing. Every single thing by brand maker x is crap and has no redeeming features. Anyone who plays brand y is an idiot who has thrown his (because often girls aren’t allowed to even look at let alone use this stuff) money away and will never sound like Stevie Ray Vaughn or Steve Vai using brand z. Brand Xx is the only thing worth using and only the brain damaged would think otherwise. You don’t watch movie P by x producer because x producer has no skills. (Even if x producer had been at the top of the industry for 30 years, because one thing Hollywood loves is a lack of talent and high risk projects).

Tubes are to the novice (like me) confusing and esoteric. I thank all of you experts for helping me learn.
 

Bendyha

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The STRs are Chinese I think - Ruby sells them as STRs too they have C in the model name. The JJs are branded Y for Yugoslavia. The Sovs are branded R......

STR stands for "Special Test Requirement" , It may well be that the ones marked STR from Ruby and Tube Amp Doctor are Chinese, but the term goes back quite a long way, and was used by many brands/manufacturers.

Some sources will tell you that it stands for "Special Tube Request", but this is a fallacy.
 

Silverface

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In my observation there are two internets: the expert internet - places like here, gretsch talk, mandolin cafe, a Subaru forum I lurk, where the information is considered, smart and if wrong usually inadvertent and quickly corrected.

One has to be careful even at sites like the TDPRI (which, honestly, I would not consider an "expert" site like I would the Amp Garage). Until you spend some time on the forum "vetting" regular contributors caution is advised - an answer could be coming from an professional tech, experienced part-timer, a very well trained amp owner that does his own tech work, an enthusiastic but inexperienced new tube amp owner that loves to "cut and paste" stuff that "sounds smart" without having a clue what it means, or a 13 year old kid that plays only XBox One but loves to type.

And even experienced techs make mistakes now and then. be cautious, vet your sources and don't take single posts (or groups of "hype" posts) as gospel.
 

dlew919

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One has to be careful even at sites like the TDPRI (which, honestly, I would not consider an "expert" site like I would the Amp Garage). Until you spend some time on the forum "vetting" regular contributors caution is advised - an answer could be coming from an professional tech, experienced part-timer, a very well trained amp owner that does his own tech work, an enthusiastic but inexperienced new tube amp owner that loves to "cut and paste" stuff that "sounds smart" without having a clue what it means, or a 13 year old kid that plays only XBox One but loves to type.

And even experienced techs make mistakes now and then. be cautious, vet your sources and don't take single posts (or groups of "hype" posts) as gospel.

Oh, for sure. You still have to weigh the stuff you get. People are human. Mistakes are made. Personal experiences differ. Some people are convinced of their wrong rightness. But there’s not that level of snark here. It does exist but it’s usually tempered.
 

Bendyha

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I suppose they could be military, but you have to watch the voltage.

I'm not sure, the 6П3С-E could be the Soviet military version of the 6П3С............and there is also the premium version, the 1540, of which I have only managed to track down a copy of the OTK sheet that came with the tube.

It could be similar to the way the 6V6GT came in the versions; Domestic -6П6С, Military - 6П6С-Y2, 6П11С, Premium "aerospace and nuclear" - 1515

I was reading in a russian forum, from a guy who appeared to have worked in the tube making industry, who said they made several closely related tubes to the 6L6, as the order required; sort of 6L6-STR....these included several I haven't looked into yet. - 6П2М, 6Л6М, 7072

Here the 1540 sheet.

upload_2018-8-4_13-38-42.png
upload_2018-8-4_13-48-37.png
 

radiocaster

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I was reading in a russian forum, from a guy who appeared to have worked in the tube making industry, who said they made several closely related tubes to the 6L6, as the order required; sort of 6L6-STR....these included several I haven't looked into yet. - 6П2М, 6Л6М, 7072
That doesn't seem right.

П is actually the letter for beam tetrode or pentode, if Л was used for something, it meant something else.

Also М would mean some other kind of base, not octal.

7027 does exist, it's a Western tube compatible with 6L6 but some were made not long ago in Saratov.
 

Bendyha

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That doesn't seem right.

П is actually the letter for beam tetrode or pentode, if Л was used for something, it meant something else.

Also М would mean some other kind of base, not octal.

7027 does exist, it's a Western tube compatible with 6L6 but some were made not long ago in Saratov.

As I said, I haven't looked into those last tubes, just wrote what was stated.................I'm more of a 6V6 fanatic...

but,
Л translates into L , so 6Л6М would be 6L6M, so there maybe something in it?
One does see Russians refering to the tube western 6L6 as a 6Л6, maybe it was his way of meaning a Metal 6L6, rather than the glass G or GT.
But as you say, a П (P) is what one might expect.
 
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radiocaster

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As I said, I haven't looked into those last tubes, just wrote what was stated.................I'm more of a 6V6 fanatic...

but,
Л translates into L , so 6Л6М would be 6L6M, so there maybe something in it?
One does see Russians refering to the tube western 6L6 as a 6Л6, maybe it was his way of meaning a Metal 6L6, rather than the glass G or GT.
But as you say, a П (P) is what one might expect.
6 is heater voltage
Л means beam but not beam tetrode
6 second number is just a number they assign to the series
М is a small octal base

https://intellect.ml/radiolampy-proizvodstva-sssr-rossii-535

in English:
https://www.audioasylum.com/messages/tubes/223386/soviet-tubes-post-1950-nomenclature

I'm thinking a В (V) at the end means military.
 
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radiocaster

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Here's what I was saying about internet nonsense, post #5 in this thread.
https://www.thegearpage.net/board/index.php?threads/6p3s-russian-tubes-anyone-try-these.1048828/

The regular 6P3S is not similar to any known current Russian tube, especially Sovtek or EH.

Here it is with an EH 6L6. It lacks silver paint on the top, the plate is of a different shape and the holes are different, and the plate is in a different place. The size of the plate is about the same though, and the plate looks like it could have been made in the same factory (which it has been).
tubes4.JPG

tubes5.JPG

tubes6.JPG

tubes3.JPG




This one is actually a 5881/6L6WGC (the last part just denotes the wafer base), which the poster in that thread identified as identical to the 6P3S. Even the plate is of a different size.
tubes1.JPG

tubes2.JPG


And besides the look, I've tried a pair of those 6P3S in an amp that the bias starts at around 460V and there's no way to keep them from redplating. The other two tubes, the EH and Sovtek can handle it fine in there.

The 6P3S did work fine in the Ramparte, where the plate voltage is under 400V. The voltage on the second grid is a bit over what is on the datasheet, but I haven't had it in there long enough to know if it's a problem.

A lot of people seem to say that the 6P3S-E can handle much higher voltages than what is stated on the datasheet. I do not have any to try out, although I would like to. They certainly look like the Sovtek 5881 in the pics I've seen.
 

zombiwoof

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The STRs are Chinese I think - Ruby sells them as STRs too they have C in the model name. The JJs are branded Y for Yugoslavia. The Sovs are branded R.

Mesa burns them in and matches them.

Why would JJ's be branded Y for Yugoslavia, they are made in Czechoslovakia?. The only Yugo tubes I know of were the EI's.
Al
 

radiocaster

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This is also interesting. The one on the left is an EHX 6L6, Sovtek 5881 in the middle, Tube Town 5881 at right, obviously all made in the same factory, and the Tube Town one is no longer available under that name.
5881-dis1.JPG

The EHX one is obviously different, different and longer plate and it is a true 30W 6L6. The ones on the right seem the same, except the getter is different on the Tube Town.
5881-dis2.JPG
5881-dis3.JPG
The 6L6 interestingly has almost the same getter as the Sovtek 5881. Well, one is a tiny bit shinier but they are the same size, unlike the smaller getter on the Tube Town. Also no groove on the 6L6 getter.
5881-6l6-getters.JPG

Tube Town ratings, 25W plate dissipation!
5881-dis4.JPG

Is this the same for all Sovtek 5881s?? The Soviet datasheets do not seem right, as others have pointed out, assuming this is the same as the 6P3S-E.
 
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SoK66

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The confusion comes from the tube marketing characters' bad practice of labelling suposedly "ruggedized" 6L6GCs as 5881s. A true 5881 is a 23w tube, a 6l6GC is a 30w tube. a "ruggedized" (what does that word reall mean?) true 5881 is a 6L6WGC, a 26w tube. Sylvania started making a very stout 6L6GC STR and that suffix has been badied about ad nauseum as well. All pretty simple but made confusing.
 

Henry Mars

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I have 40 yr old 6L6 pwr tubes in one of my Peavey amps .... still ticking and still sound really good.
Nothing wrong with them.
The new 6V6 tubes leave a lot to be desired. I have two amps that run them and they burn up quick.
 

Telecastoff1

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"I have 40 yr old 6L6 pwr tubes in one of my Peavey amps .... still ticking and still sound really good.
Nothing wrong with them."


#1
 

uriah1

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Wow. this is old...but I would add

There is a low volt vers of the 6L6 called 6L6GB if I recall. Prob closer to the 5881
 




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