I like passion!What WASP has done in The Crimson Idol is pure symphony. That album goes much beyond any heavy metal album has gone. It is a story beyond time. WASP has no age, it is pure gold guys.
Tube rolling thread | UltraSonic Studios
- Thread starter OctavianH
- Start date
I am a simple guy, but bands like WASP make me just dream. WASP and Led Zeppelin.
Ah, speaking abut Led Zeppelin makes me post this. I love the first album. Babe I'm gonna leave you is fabulous.
What can you say about Robert Plant? Words cannot describe. I have no words, he and Ozzy changed my life.
Speaking about Ozzy led me to the old Sabbath recordings. They were excellent in the 70s before getting well known. I love old Sabbath.
And I am listening to obscure piano music using neglected tubes. We live in the same universe! Music is music.
Sounds interesting. My uncle had a piano in his house, he was a piano and violin theacher.
I agree but in my view it is much easier to evaluate how natural an audio system sounds when you listen to acoustical music. Even if I claim here that this is better than that, honestly I doubt that with rock music you can truly evaluate this. I also share the same doubts to people listening to EDM or other genres. Acoustical music is for me the reference and you are closer than me to this.
Today I observed a dark coating on the 6AT6/DH77 tubes. I am, in my view, within specs by keeping these at 2.5mA but I guess a better way would be to put them at around 1mA. Oblivion was biasing at 1mA in input stage so I bet these would sound fabulous on that amplifier.
This fact leads me to the question, how would these bias on a cathode bias amplifier? I mean you cannot set anything on that one and you have a resistor. Are these safe to be used on any amplifier? Here I struggle with them feeling I'm forcing a bit at around 2-2.5mA. They heat around 60C so nothing extraordinary.
This fact leads me to the question, how would these bias on a cathode bias amplifier? I mean you cannot set anything on that one and you have a resistor. Are these safe to be used on any amplifier? Here I struggle with them feeling I'm forcing a bit at around 2-2.5mA. They heat around 60C so nothing extraordinary.
I have decided to store the 6AT6/DH77 because I think that using those at 2-3mA will decrease their life without reason. A possible solution for me would be to use a double adapter which connects 2 in parallel and then reduce by half the current but well, I am not that crazy. I have a quad but I prefer to use other tubes instead of going on this path. One thing is for sure, there is a great potential in these low current high mu tubes and one day maybe I'll have a different amplifier to enjoy them.
SFR P17C. We spoke about this tube in the past, when discussing about the French old tubes which are highly regarded on Lampizator threads. We also found at that time an Ebay seller with a very aggressive marketing on these, stating these are the "4654 Killer". So I had to admit he raised curiosity, this is exactly his intention, to make me wonder why the SFR P17C is better than the already highly regarded and more well known Philips EL50/4654. He mentions there also OS1, SRS551 and most probably this should be the killer also for the Tungsram OS18/600.
But my biggest problem was that his pricing was not matching my price plan and investment plans in order to fully investigate the old european pentodes. If you start a road like me and try to follow family of tubes, you also need to put in place some strict rules so your journey will not lead you to bankrupcy. In short, he wanted my kidney and I did not want to loose it because I like beer. No problem, patience made me wait until I was able to get a pair, not tested nor NOS NIB, but good enough for me to investigate who killed the EL50. Here we are, SFR P17C, the "4654 killer" in front of his victim and near a sibling:
Now honestly only if you look at this photo you realize that the 4654 killer is in fact, no 4654. It looks more like a french version of the PE06/40P we have in the left side than a sibling of our already known EL50/4654. And the ultimate proof to this statement are the measurements. 4654 needs around -15V for 20mA on my amp and the PE06/40N is much stronger, goes around -28V. Guess what, I measured these for grid bias for my amp (200V/20mA) and one needs -28.6V while the other -28.1V. Very close and nicely matched! Thank you! So we have the proof, SFR P17C is a french more romantic version of the PE06/40P (or N or E, choose whatever hase you like, P8A is the worst anyway).
This is how it looks in detail, "AIR" means most probably French Air Forces? I wonder on what they used these. Some double rectangle getters, these have to be newer than the others. I see not date code, but all have those S/N on them, it would be excellent if there is an archive for this and I can localize these in time. I have no idea.
The nice dark brown bases are similar with some EL3N black glass I bought from France which I assumed were RT (those markings on the base similar with RT tubes).
So what remains? Let's put these on the amplifier. I put back the Fivre 6SL7 because that is the best allrounder and I tried it extensively with the Philips 4654/EL50.
I will spend some time with these and I will also keep them forever in these adapters. I do not want to risc to damage something because I'll never get another pair while keeping both my kidneys around. So well, this is what happens when some tubes become famous...
Soundwise these remind me on the RT 4654 I briefly tried some weeks ago. That more creamy and romantic, darker sound. But again, strictly technical speaking these are less transparent than the Philips, I feel that separation decreases in favour of a more relaxed presentation. For sure good sound, and in my view these are identical sounding to the PE06/40N with brown base and E-code.
I will leave this on the amp and think to pair them with a brighter / sharper input which has also more aggressivity in high frequency area to combat the darker tone. I really want to explore more this signature now that I arrived to the conclusion that all these sound close. A good test here would be with RT EL39 but that one is not a part of my collection, preferred to obtain the same type of sound going sideways to older siblings.
In conclusion, SFR P17C, a french darker sounding variation of the PE06/40 tube. Much less aggresive than the KL/DUF black base pair I have here. French romanticism. Has it killed the EL50? I doubt, in my view is more a matter of synergy. This is sometimes more important than the quatity of a tube type. For an amplifier which has a more distorted signature these might be better than the Philips, of course maybe for other musical genres than what I am listening. There are always usage scenarios where one can beat the other, but in my view nobody killed anyone, I am glad to be able to experience both and I am a little bit dissapointed about the pricing of the french tubes. This means we have to discover more unknown types to counter this phenomenon.
But my biggest problem was that his pricing was not matching my price plan and investment plans in order to fully investigate the old european pentodes. If you start a road like me and try to follow family of tubes, you also need to put in place some strict rules so your journey will not lead you to bankrupcy. In short, he wanted my kidney and I did not want to loose it because I like beer. No problem, patience made me wait until I was able to get a pair, not tested nor NOS NIB, but good enough for me to investigate who killed the EL50. Here we are, SFR P17C, the "4654 killer" in front of his victim and near a sibling:
Now honestly only if you look at this photo you realize that the 4654 killer is in fact, no 4654. It looks more like a french version of the PE06/40P we have in the left side than a sibling of our already known EL50/4654. And the ultimate proof to this statement are the measurements. 4654 needs around -15V for 20mA on my amp and the PE06/40N is much stronger, goes around -28V. Guess what, I measured these for grid bias for my amp (200V/20mA) and one needs -28.6V while the other -28.1V. Very close and nicely matched! Thank you! So we have the proof, SFR P17C is a french more romantic version of the PE06/40P (or N or E, choose whatever hase you like, P8A is the worst anyway).
This is how it looks in detail, "AIR" means most probably French Air Forces? I wonder on what they used these. Some double rectangle getters, these have to be newer than the others. I see not date code, but all have those S/N on them, it would be excellent if there is an archive for this and I can localize these in time. I have no idea.
The nice dark brown bases are similar with some EL3N black glass I bought from France which I assumed were RT (those markings on the base similar with RT tubes).
So what remains? Let's put these on the amplifier. I put back the Fivre 6SL7 because that is the best allrounder and I tried it extensively with the Philips 4654/EL50.
I will spend some time with these and I will also keep them forever in these adapters. I do not want to risc to damage something because I'll never get another pair while keeping both my kidneys around. So well, this is what happens when some tubes become famous...
Soundwise these remind me on the RT 4654 I briefly tried some weeks ago. That more creamy and romantic, darker sound. But again, strictly technical speaking these are less transparent than the Philips, I feel that separation decreases in favour of a more relaxed presentation. For sure good sound, and in my view these are identical sounding to the PE06/40N with brown base and E-code.
I will leave this on the amp and think to pair them with a brighter / sharper input which has also more aggressivity in high frequency area to combat the darker tone. I really want to explore more this signature now that I arrived to the conclusion that all these sound close. A good test here would be with RT EL39 but that one is not a part of my collection, preferred to obtain the same type of sound going sideways to older siblings.
In conclusion, SFR P17C, a french darker sounding variation of the PE06/40 tube. Much less aggresive than the KL/DUF black base pair I have here. French romanticism. Has it killed the EL50? I doubt, in my view is more a matter of synergy. This is sometimes more important than the quatity of a tube type. For an amplifier which has a more distorted signature these might be better than the Philips, of course maybe for other musical genres than what I am listening. There are always usage scenarios where one can beat the other, but in my view nobody killed anyone, I am glad to be able to experience both and I am a little bit dissapointed about the pricing of the french tubes. This means we have to discover more unknown types to counter this phenomenon.
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Regarding getters, I see that these have some double rectangle getters on each side.
And regarding date codes, at first I wanted to check those S/N and while one was something like /430224 which could be easily thought as 43.02.24 and well, in that case these are from the 40s, on the other one the number started with 88 so the rule does not make sense anymore and we surely have a S/N and not a date. My instinct tells me these are from the 60s. On the side where AIR is marked, I see an 838 and 841 which could be a kind of YWW like 8-38 and 8-41, these being made in 1968 at 3 weeks distance? Might be. If someone knows more please share.
PS. A crazy comparison but listening more and more to these make me think about differences between copper interconnects vs silver interconnects. Philips 4654 sounds more dry like silver, being sometimes dull on midrange while P17C sounds like copper being less resolving but somehow more analogue. I know there is a long debate of copper vs silver interconnects, I do not want to summon here the Cable Inquisition, but if someone hears these differences like me can also understand more about this. Bass is more in quantity than Philips, so if you like bass then these might suit you better.
And regarding date codes, at first I wanted to check those S/N and while one was something like /430224 which could be easily thought as 43.02.24 and well, in that case these are from the 40s, on the other one the number started with 88 so the rule does not make sense anymore and we surely have a S/N and not a date. My instinct tells me these are from the 60s. On the side where AIR is marked, I see an 838 and 841 which could be a kind of YWW like 8-38 and 8-41, these being made in 1968 at 3 weeks distance? Might be. If someone knows more please share.
PS. A crazy comparison but listening more and more to these make me think about differences between copper interconnects vs silver interconnects. Philips 4654 sounds more dry like silver, being sometimes dull on midrange while P17C sounds like copper being less resolving but somehow more analogue. I know there is a long debate of copper vs silver interconnects, I do not want to summon here the Cable Inquisition, but if someone hears these differences like me can also understand more about this. Bass is more in quantity than Philips, so if you like bass then these might suit you better.
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Citroën copper tubes for acoustical music - I love it! How do you say 'wonderful' in French?
I will use my very advanced french language skills obtained during 4 years in High School : "marvelloise!". Please do not ask me something else.
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The story of the 6AG7. I never heard of this tube but got one by mistake. Looks nice, seems an 9W pentode.
I never thought to try these, I would need a pair anyway but it seems some others already did that here. From what I see these work in the 6SJ7 -> something adapters. In my case my adapters 6SJ7 -> are built towards 6J5 but should also work in 6V6. I measured that I need around -9.3V for 180V/4mA and this means I can put in the other channel one Mullard ECH3 and then just check how this sounds in the other channel. I might do this in the future, I doubt anyone used around 6AG7 and they are dirty cheap on Ebay, 2-3 USD in the US.
I never thought to try these, I would need a pair anyway but it seems some others already did that here. From what I see these work in the 6SJ7 -> something adapters. In my case my adapters 6SJ7 -> are built towards 6J5 but should also work in 6V6. I measured that I need around -9.3V for 180V/4mA and this means I can put in the other channel one Mullard ECH3 and then just check how this sounds in the other channel. I might do this in the future, I doubt anyone used around 6AG7 and they are dirty cheap on Ebay, 2-3 USD in the US.
In the last days I have tried to evaluate how I can fix the P17C sound making it more sharp, neutral and also enhancing its tone to a more lively and vivid presentation. As I said, all is a matter of synergy and while I understand that some might prefer the SFR P17C to the 4654 made by Philips, in my view there are some things above the tube type related to richness of the tone (what I call vivid making all the time an analogy with photos) which cannot be solved by a different amplifier or operating point of a tube.
Fivre 6SL7 was not a good pairing to the SFR P17C, at least not for me, so I tried to go towards Telefunken ECC801S (12AT7 variation) but the Telefunken sound was too sterile and dry and not a good match, was lifeless. Then I went to the Jack of all trades, ITT Lorenz E8CC, which was definitely much better. I can say I was 99% pleased but the problem is that you cannot fix the richness of the tone with a combo, you might fix several things but the "common" tubes cannot bring vividness. So I was again with the elephant in the room, who to elevate P17C to a higher tier of sound. Luckily for me, the Philips EBC3 is here to help. A neutral, brightish tube with sharp highs and less musical mids. This had to do the trick so I had to try it.
And yes, this was in my view another step above the E88CC. Same style of sound but more vivid. This is a good proof that I will have to try EBC3 with more of the previously used tubes and see what is going on, for example with EL34 which seem to me relatively fuzzy sounding but might get better with them. But this will be done later, I want to spend more time with P17C, maybe weeks, to see how far I can go with them towards the sound I like.
Fivre 6SL7 was not a good pairing to the SFR P17C, at least not for me, so I tried to go towards Telefunken ECC801S (12AT7 variation) but the Telefunken sound was too sterile and dry and not a good match, was lifeless. Then I went to the Jack of all trades, ITT Lorenz E8CC, which was definitely much better. I can say I was 99% pleased but the problem is that you cannot fix the richness of the tone with a combo, you might fix several things but the "common" tubes cannot bring vividness. So I was again with the elephant in the room, who to elevate P17C to a higher tier of sound. Luckily for me, the Philips EBC3 is here to help. A neutral, brightish tube with sharp highs and less musical mids. This had to do the trick so I had to try it.
And yes, this was in my view another step above the E88CC. Same style of sound but more vivid. This is a good proof that I will have to try EBC3 with more of the previously used tubes and see what is going on, for example with EL34 which seem to me relatively fuzzy sounding but might get better with them. But this will be done later, I want to spend more time with P17C, maybe weeks, to see how far I can go with them towards the sound I like.
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