[Isaacc7]

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.

Yeah, I keep coming back to this realization. But then one of my tubes gets noisy, or just dies and I’m right back to worrying about having enough for the rest of my life. It’s a sickness lol.

 

[OctavianH]

Whenever something goes against my expectation, I double check in the next day. So today I wanted to hear again these F-code EL82 and see if indeed, I was not crazy last night. If you'd asked me a few days ago if I can consider decent a tube made by La Radiotechnique in Suresnes I would say, well, you know... I think Suresnes and Chartres are the ones I like the least from what I was able to hear. But not always a drawback on input stage will manifest in the same way as output. So this kind of relaxed and fuzzy signature, quite euphonic, lacking dynamics and separation, might be quite nice on output.

I'll not put this tube on any kind of podium, even if it surpassed a lot my expectations, but I will have much higher ones about the Mullard pair. I was lucky to obtain 2 pairs of different construction in the same lot and avoid another shipping costs. This is why I like bundles of tubes, searching in them makes everyday Christmas. LOL

I will have to go back to EL81 from where all this started. I have a feeling that EL85 and EL82 will put in danger its place. At least for Mullards, because on EL81 we have those Siemens (which I consider to be in fact Tesla) which are very different from the bunch being much more on the neutral side. Maybe this is why Tomas has chosen them as stock in Oblivion (except the price). So we reach the conclusion that not only a tube type matters but also diversity on manufacturing plants. Diversity matters. Now Netflix can hire me.

Later edit:
I think I understood what fascinated me on EL42 and why I find somehow similar this pair of EL82. It's that OTL type of sound I was used to listen in the past. When we moved to these SET amps we went towards a more technical and speedy sound. We got more detail, separation, soundstage and on the paper everything was a plus. But I remember that sweet fuzziness of Elise. It was definitely not able to compete with Eternity, but had something relaxing and smooth. I think that EL42 and EL82 bring my SET amp more towards an OTL type of sound. Less technical but enjoyable. This is not good for everyday listening but it adds something nice from time to time. A good addition to my tube collection, and a cheap one also.

 

[OctavianH]

Curiosity made me switch to the B-code EL82. Expectations were quite high, but here we have a dissappointment. Well, this wet sound of B-code tubes does not pair nicely with the overall relaxed tone of EL82. Bass is too fuzzy, less impact, a lot of sweet mids but somehow less coherence. It reminds me on EL34. I thought I'll never saw this but I'll switch back to F-code. Goes better on this type of sound, more creamy. Mullard is airy but... misses some impact. I even tried to put the Fivre 6SL7 which went well with a lot of Mullards, but could not save it. Added some bass but still, not as I would like it. I remember now why I put EL34 and EL38 made by Mullard behind 807 for example. This is very close to what I disliked on those.

But before that, I tried to make a better picture of the disc/vertical getter of the F-code. That disc reflecs the light and makes it glow in that special way. Not all pieces glow in the same way because the disc on some of them angled.

And now let's put the Mullard B-code EL82 into storage. It's for me the EL34 of the poor. Might sound an idea less powerful than EL34 but the feeling is the same. So if you want a cheap alternative to Mullard EL34, EL82 is your choice (if you amp can accomodate it, it has much lower max ratings like for example Vplate max = 250V). They even bias close, -17.5V instead of around -16.5V in my case.

 

[triod750]

Interesting findings indeed.

 

[OctavianH]

Time will tell us more, it's a beginning. I was not able to read too much about these so I guess not many tried them. We have to start from somewhere. I knew about EL84 which is compared by many with EL34. Not quite sure why since in my view, they are quite different, with different gain and so on. Anyway, maybe they sound similar on other amps.

 

[OctavianH]

I had a try yesterday of the Marconi 6AT6 in my adapters to 6J5 but I heard some hum with EL82. The same hum I heard when trying too high gain tubes in both stages. So my experiments with 6AT6 are postponed until I investigate more the situation. Of course, I put these at 2.5mA as I was planning but I have a feeling it's a little bit too much for them. We will see.

In the meantime I just realized that my 6CG7 adapters work perfectly for 6922. Good catch, it was obvious if you put those pinouts on a table. I told you that the tube rolling should began with pinout investigation. If you put all those one near the other you start seeing things. LOL

Excellent! I'll use this 6CG7 adapter with E188C or 6BQ7 or whatever works on 6922 one. I do not quite like the 6CG7, are a kind of 6SN7.

 

[OctavianH]

But since it is Friday Beerday we need to go towards a simple setup, and this is a good point for me to return to EL34 and check it in the context of ECC40 and other nice stuff we discovered lately. But first, let's go with a classic setup. Fivre 6SL7 with Philips EL34 xf5 / L1L. Oldies but goldies.

When I ordered Eternity my plan was to get rid of adapters forever, but we all know what happened afterwards. Well, it happens.

By the way since I've started to look more and more towards date codes and factory codes I went again here to remember what was the situation with these tubes. And I see that a xf5 / Lxx tube is described as Sittard, NL.

Now, well, L was not Mazda Bruxelles? Something is rotten in Denmark.

 

[triod750]

Xf is the type code for EL34 and next digit is the change code, for example 4 or 5 or something. Then comes the factory code where the first digit is factory. If you find X there, this means Sittard and L should mean Mazda Bruxelles.
XF is the type code for 12DJ8. I can't find xf as type code anywhere. Some tubes had a change in type code, such as 12AT7/ECC81 where the first was Tk, later changed to YK.

Where did you find this description?

 

[OctavianH]

Xf is the type code for EL34 and next digit is the change code, for example 4 or 5 or something. Then comes the factory code where the first digit is factory. If you find X there, this means Sittard and L should mean Mazda Bruxelles.
XF is the type code for 12DJ8. I can't find xf as type code anywhere. Some tubes had a change in type code, such as 12AT7/ECC81 where the first was Tk, later changed to YK.

Where did you find this description?

Here.
http://www.tube-classics.de/TC/Tubes/Valvo EL34/EL34.htm

 

[triod750]

I looked at his 'xf1 BXX' from Blackburn. If you magnify the photo you don't see 'xf' but XF or maybe Xf. He is careless.

 

[OctavianH]

Yes, some EL34 were SY (I guess metal base ones), then Xf but in some Philips manuals I see XE or XE2. Too many rules and too many exceptions.

 

[LobalWarming]

Yes, some EL34 were SY (I guess metal base ones), then Xf but in some Philips manuals I see XE or XE2. Too many rules and too many exceptions.

Pretty sure mid-20th century tube manufacturers didn't consider future audiophiles zipping around in their flying cars scanning tube production data on their handheld UNIVACs.

 

[OctavianH]

Pretty sure mid-20th century tube manufacturers didn't consider future audiophiles zipping around in their flying cars scanning tube production data on their handheld UNIVACs.

Flying cars you said? Uhm.... well... audio in 2023. LOL

 

[OctavianH]

But since I arrived at these Philips EL34 double D-getter "made in Holland" with L code, let's test a myth. People say that these sound similar with the EL34 metal base. The others say that 4654K sound similar with EL34 metal base. Well, I do not have EL34 metal base because I was greedy and kept both my kidneys but well, we can do an indirect test. If a=b and b=c we expect a=c? Not in audio world and in this myth.

Now, to believe the myth, these even bias identically on my amp, I have not touch anything. Then both have "L" codes and similar getters.

But on the amp, well 4654K sounds sharper, better defined and with more clarity, tighter bass, more detail in the high frequency range. What to say, better, even more dynamic. Well, EL34 cannot touch this and if I remember correctly these were some of my favourite EL34. For sure is not the perfect test, but we do what we can do. Myth busted? I have no idea, I'll never listen to EL34 metal base since I doubt any seller would make me an offer in my newly imposed price range of 20 EUR/tube. So I'll never know.

Now I guess I can return to my 3 EUR tubes to continue with audiophile revelations.

 

[Isaacc7]

One or more of my GE 6bg6ga tubes started getting pretty noisy so I cut short their time. Moved on to the Sylvania 6bg6ga triode mode. Using them with the Fivre triode wired 12j7 tubes gave me a very… smooth sound. It’s the best word I can come up with. I think this is what people mean when they say sound is liquid. I found it a bit unnerving for some reason, it didn’t sound natural. Artificial in a natural way? I can’t figure out how to describe the sound, sorry. Took the Fivre out and tried the Tung Sol BGRP 12sn7. Oh come on! The liquid effect was amplified, my speakers were positively dripping lol. No, not what I like at all.

I remembered that Tomas had actually designed my amp with 6sl7 in mind and that I could use 6sn7 “If you want to.” I don’t own nearly the variety of 6sl7 as *sn7. Before digging for some off them I noticed a pair of Tung Sol 6c8g tubes which are close-ish to 6sl7 or at least closer than the 6sn7. Like the Tung Sol 12sn7, I have had a difficult time finding a good match with the 6c8g despite both of those tubes great reputation.

The 6c8g with the Sylvanias are a really good combo. It still has that smooth character but now there is more something. Sorry, again I’m having trouble describing what I’m hearing. Compared to the 12sn7, the 6c8g is giving back some presence or depth to the sound. At first I thought this combo was bass shy but I think it is just more picky about recording quality. Well recorded music has a tremendous bottom end. Think I the c3m/vt60a combo goes lower and dryer but this is satisfying. Will let these cook for the rest of the week I think.