It's important not to mix up military codes with 'civilian consumer codes'. And type codes changed for some tubes in the Philips code system too. ECC81/12AT7 can have either Tk (early) or VF (later) type code. Same with some other tubes too.
Tube rolling thread | UltraSonic Studios
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66 is the early type code for EL85. The '0' means first version/batch. rW is the later type code and '2' is the third version/batch. These numbers are the change codes.
The above information might be correct.
The above information might be correct.
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Just put the ugly ducklings to work. All goes a little bit towards I was expecting from Mullard. More wet, euphonic sound, but still not that retro analogue sound of EL42. I will spend some days with each one of them and then compare 1:1 the EL85 and EL42 made in Blackburn.
I never thought there is such a difference between R-code and B-code. But I do not remember if I listened to another R-code.
PS. I do not know why but I feel these small pentodes sound an idea more congested than, for example, big EL34. Maybe this is why the wet sound of Mullard goes well to counter balance an idea the signature. Of course, might be also my mind because I doubt that the glass size has a direct effect on soundstage.
I never thought there is such a difference between R-code and B-code. But I do not remember if I listened to another R-code.
PS. I do not know why but I feel these small pentodes sound an idea more congested than, for example, big EL34. Maybe this is why the wet sound of Mullard goes well to counter balance an idea the signature. Of course, might be also my mind because I doubt that the glass size has a direct effect on soundstage.
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I decided to spend more time with the R-code and see where things are going, because the B-code is clear to me.
EL85 is a good chance for me to try a Valvo ECC808 I had in plan to test for a long time. It was borrowed to me but I never found the context for it.
These R-codes Mullard EL85 are very tight and detailed, but an idea dry. Most probably all these attributes go hand in hand because when you put a tube to compensate one of them, you start to realize you loose an idea also from the others and, in the end, there is no perfect solution, only a compromise which makes you stop searching. The "shouty" Valvo with very high gain, ECC808 is definitely a good choice here to put some salt and pepper. I keep calling Valvo "shouty" thinking about my ECC40, but I realized that tube flavour decreases with gain. When you go towards 12AX7 or ECC808 you barely detect any flavour. Or maybe is just my impression. It's true I never went around mu 100 too often keeping mostly my input stage around 70 with 6SL7 or 12AT7.
These R-codes Mullard EL85 are very tight and detailed, but an idea dry. Most probably all these attributes go hand in hand because when you put a tube to compensate one of them, you start to realize you loose an idea also from the others and, in the end, there is no perfect solution, only a compromise which makes you stop searching. The "shouty" Valvo with very high gain, ECC808 is definitely a good choice here to put some salt and pepper. I keep calling Valvo "shouty" thinking about my ECC40, but I realized that tube flavour decreases with gain. When you go towards 12AX7 or ECC808 you barely detect any flavour. Or maybe is just my impression. It's true I never went around mu 100 too often keeping mostly my input stage around 70 with 6SL7 or 12AT7.
In my search for a perfect synergy of these Mullard R-code EL85 I arrived again at this Siemens E88CC. This is a fabulous tube, one of the best I've heard and I've heard many. It has a very lively presentation, detailed and very natural timbre. One of a kind. But the problem is that I never found enough info about this kind of stamped date code. A6 6J. Does anyone know how to decypher these?
I found different opinions, but many go towards:
A = E88CC (T)
6= revision (R)
6 = 1976 (Y) ?
J = October (M) ?
I think I had this problem a few months ago, well, everytime I listen to this one I realize I do not fully understand this kind of date codes.
I'll read more about these and a good start is here.
I found different opinions, but many go towards:
A = E88CC (T)
6= revision (R)
6 = 1976 (Y) ?
J = October (M) ?
I think I had this problem a few months ago, well, everytime I listen to this one I realize I do not fully understand this kind of date codes.
I'll read more about these and a good start is here.
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Isaacc7
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The GE 6bg6ga and Mullard cv535 are also proving to be a good combo. This sounds more “accurate” with perhaps more air on tap as compared to the TS BGRP. The TS have the edge in richness though. I’ll keep this combo in till Wednesday, my next day off. Next up is the Sylvania/Philips 6bg6ga. These are the ones with the guts of the Sylvania 7027a in them. I will run them at the regular 6bg6 specs first but will try higher voltages later on.
While I will not try soon any 6BG6GA I guess I'll soon come with something which might be interesting to you. Stay tuned.
And the days passed and Mullard R-code EL85 with ITT Lorenz branded Siemens E88CC became one of my favourite combos. There is something very special about this combination, a thick but somehow fluid sound which has an excellent level of detail. Yep, I know, sounds cliché but this is how I see it. I guess 99% of what people post here is cliché. EL85 seems to be a very interesting option for me and I will definitely follow it and search for other versions than the ones I have. While it does not sound similar to EL42 it keeps a decent level of coherence and adds some dynamics to the table, this bringing me very close to where I always wanted to be, in terms of sound signature.
EL85 is here to stay, I still need to play more with the B-code and compare it 1:1 with the Mullard EL42 made in Blackburn. But tomorrow another story will start. 6AT6 and EL82 will be our guests here. These before going to some bigger pentodes, some relatives of EL36 but not EL36, however electrically equivalent. Yeap, when people go on the main road and try EL36 I go sideways trying something else. It will be very interesting, I promise that.
EL82 will bring the end of a circle. EL81/82/83/84/85 were tried on Eternity. EL86 was a good try but I am not disposed to spend too much. After EL82 and 6AT6 (maybe 6AV6) and the big pentode, I still think to try EL42 on input. Then? Hell knows, we will let others find new tube types or maybe we will try 1000 new ones.
EL85 is here to stay, I still need to play more with the B-code and compare it 1:1 with the Mullard EL42 made in Blackburn. But tomorrow another story will start. 6AT6 and EL82 will be our guests here. These before going to some bigger pentodes, some relatives of EL36 but not EL36, however electrically equivalent. Yeap, when people go on the main road and try EL36 I go sideways trying something else. It will be very interesting, I promise that.
EL82 will bring the end of a circle. EL81/82/83/84/85 were tried on Eternity. EL86 was a good try but I am not disposed to spend too much. After EL82 and 6AT6 (maybe 6AV6) and the big pentode, I still think to try EL42 on input. Then? Hell knows, we will let others find new tube types or maybe we will try 1000 new ones.
The real challenge when buying tubes around 3-7 EUR like me is to avoid hoarding. Well, it seems I have failed another test. At least I'll not have problems to pair them.
It's true I always search for packs, to have at least the value of shipping. No problem, said and done. Welcome 6AT6 and EL82!
It's true I always search for packs, to have at least the value of shipping. No problem, said and done. Welcome 6AT6 and EL82!
And guess what? EL82 are B-codes Mullards. Not bad. Boxes in perfect condition, was a fight to open. Tt1 / B2H2.
Well, B-code on the small boxes because the big boxes are something different and I'll show you what.
These are F-code, La Radiotechnique, Suresnes. Tt.0 / F5C-09 or other number. Hmm, things are getting more and more interesting. Because if I look inside them I see a kind of "vertical D-getter" oposed to a disc? I have never seen something like this. Mistery! I told you guys the real audiophile revelations come in the range of 5 EUR / tube. Others are just blinded by their pride to look where they should. LOL
Well, B-code on the small boxes because the big boxes are something different and I'll show you what.
These are F-code, La Radiotechnique, Suresnes. Tt.0 / F5C-09 or other number. Hmm, things are getting more and more interesting. Because if I look inside them I see a kind of "vertical D-getter" oposed to a disc? I have never seen something like this. Mistery! I told you guys the real audiophile revelations come in the range of 5 EUR / tube. Others are just blinded by their pride to look where they should. LOL
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But the story gets an idea more intersting when looking at the 6AT6. Well, this spanish seller was not very nice and sent me something else. 3 x 6AT6 (2 O-getter and 1 D-getter) and one 12CU5. Never heard of this one, I doubt I need it. I doubt I'll ever order something else from him.
And then some Marconi DH77 / 6AT6. Very interesting tubes.
And the 2 variants of Fivre.
The plan is to keep the 6AT6 around 2.5mA just to see how they would sound with EL81. What I call the "complete Oblivion" experience. The only problem was that Tomas was keeping these at 1mA on Oblivion and I'll force them a bit here. Tiny plates, beautiful. Who knows maybe I'll have an Oblivion in the future and these will be spare parts.
Measurements showed that B-code EL82 needs -18V for 200V/20mA. The F-code needs around -20V for 200V/20mA. The Fivre 6AT6 goes around -0.8V for 180V/2.5mA while the Marconi is around -1.3V for 180V/2.5mA. So these are the voltages for bias, for EL82 I'll use my EL84 adapters, same pinout as far as I've seen. Worked well on the tester so ... soon we will have the truth moment, the amp.
And then some Marconi DH77 / 6AT6. Very interesting tubes.
And the 2 variants of Fivre.
The plan is to keep the 6AT6 around 2.5mA just to see how they would sound with EL81. What I call the "complete Oblivion" experience. The only problem was that Tomas was keeping these at 1mA on Oblivion and I'll force them a bit here. Tiny plates, beautiful. Who knows maybe I'll have an Oblivion in the future and these will be spare parts.
Measurements showed that B-code EL82 needs -18V for 200V/20mA. The F-code needs around -20V for 200V/20mA. The Fivre 6AT6 goes around -0.8V for 180V/2.5mA while the Marconi is around -1.3V for 180V/2.5mA. So these are the voltages for bias, for EL82 I'll use my EL84 adapters, same pinout as far as I've seen. Worked well on the tester so ... soon we will have the truth moment, the amp.
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It was not easy to remove the EL85, because it sounded good and my energy for rolling is limited. But I had to try some EL82 just to see what is the situation. So I went for the one where I had the lowest expectations: F-code EL82 labelled Adzam. I remember I listened a few weeks ago to an F-code ECC40 and was quite disappointed, it did not reach my top 3 and considered it somehow lacking detail and rolled of on highs. That kind of tube you just consider "meh" and store it. However, this kind of signature it seems sounds much better on output where these Adzam EL82 sound very liquid and laid back. I might be crazy but these F-code EL82 remind me more about EL42. Not quite a good separation, not quite a fast tube, but laid back and thick, quite forgiving and sharpless. I guess I was describing the same the EL42 when I started to listen to those.
I will need months to understand EL82 and EL85 and of course revisit them near EL42 or EL81. At the moment I am just happy that the circle is complete and I got an idea about EL82. Above expectations. A slow laid back tube going well with slow music. Who would have thought? Me not one second. They are for sure helped by the energic Siemens E88CC, but were not a disappointment and the fact that I have 13 pieces is not so bad.
And these tubes are interesting also for the glow. That kind of disc near the vertical D-getter is somehow reflecting the light from the heater like a mirror. I tried to make a picture, just to show this because it looks quite interesting.
I will need months to understand EL82 and EL85 and of course revisit them near EL42 or EL81. At the moment I am just happy that the circle is complete and I got an idea about EL82. Above expectations. A slow laid back tube going well with slow music. Who would have thought? Me not one second. They are for sure helped by the energic Siemens E88CC, but were not a disappointment and the fact that I have 13 pieces is not so bad.
And these tubes are interesting also for the glow. That kind of disc near the vertical D-getter is somehow reflecting the light from the heater like a mirror. I tried to make a picture, just to show this because it looks quite interesting.
Isaacc7
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Ugh. This is me. “Ooh, this tube looks interesting. And it’s cheap? Better by a dozen…” To be fair, my amp uses quads for outputs and if I use single triodes for inputs I also needs quads. So of course I better have another set for back up. And then of course if they become one of my favorites I better have more for long term… Sure glad I like cheap-ish tubes. Although some of my previous less expensive options have gotten noticeably more expensive even in the last year or so. The vt60a and Raytheon 6f8g have both seemingly jumped in price. The vast majority of the tubes I buy start cheap and stay there though lol.The real challenge when buying tubes around 3-7 EUR like me is to avoid hoarding. Well, it seems I have failed another test. At least I'll not have problems to pair them.
It's true I always search for packs, to have at least the value of shipping. No problem, said and done. Welcome 6AT6 and EL82!
I always think about replacement and backup pairs but honestly I never had a tube to fail until now. So I guess it's hoarding.
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