Tubesteve quite right.
Like all second source stuff, my first instinct is to electrically hammer them with the Mullard as my reference. The others hold up equally to the Mullard. There is a new issue EL34 Mullard being made by the Russians. SOme institution has bought the Mullard logo.....is this Reflektor, or who ? and has anyone electrically hammered these ?
richy
Like all second source stuff, my first instinct is to electrically hammer them with the Mullard as my reference. The others hold up equally to the Mullard. There is a new issue EL34 Mullard being made by the Russians. SOme institution has bought the Mullard logo.....is this Reflektor, or who ? and has anyone electrically hammered these ?
richy
el34
the new sensor corporation , new york, bought recently: Tung-sol, Mullard etc. names. the man behind is Mike Matthews, he operates the EH/ sovtek factories with a link to svetlana fty. for me the re-issued mullards are the same as the Svetlanas as far as i can see the construction ( EL34 ). maybe they select just for different performancesand then label them..... its all about marketing. you make take that mullard el34 as good, seems to be an XF4 from the last production done.
the dimple top RFT EL34 tubes have been used in man guitar amps with no problems.the only issue is el34 dont like much more G2 voltage than 425V, despite what the manufacturer states. remember: tubes are mechanically constructed according to drawings which should be identical in dimensions.
there is not much room to change, besides the vacuum and the materials and workmanship.
i have measured quite some different EL34, the differences in curves are marginal. they react but different on higher plate voltages.
the closest construction or identical to NOS is nowadays from JJ using old tooling resp. repaired or re-newed it. but they seem to have a few quality issues.
the new sensor corporation , new york, bought recently: Tung-sol, Mullard etc. names. the man behind is Mike Matthews, he operates the EH/ sovtek factories with a link to svetlana fty. for me the re-issued mullards are the same as the Svetlanas as far as i can see the construction ( EL34 ). maybe they select just for different performancesand then label them..... its all about marketing. you make take that mullard el34 as good, seems to be an XF4 from the last production done.
the dimple top RFT EL34 tubes have been used in man guitar amps with no problems.the only issue is el34 dont like much more G2 voltage than 425V, despite what the manufacturer states. remember: tubes are mechanically constructed according to drawings which should be identical in dimensions.
there is not much room to change, besides the vacuum and the materials and workmanship.
i have measured quite some different EL34, the differences in curves are marginal. they react but different on higher plate voltages.
the closest construction or identical to NOS is nowadays from JJ using old tooling resp. repaired or re-newed it. but they seem to have a few quality issues.
El34
there is one more thing to say about new production: after observing the Shuguang factory here, it seems, the chinese learned, to improve their tubes.
after manufacturing firecrackers in glass housing for decades they got more knowledge and help from abroad to make thingss better. as this continues, they will understand, this can earn money by relaibility and quality. Some of their tubes are really good, as for example the KT66 and the newer EL34B edition. their small signal tubes perform well, but i am still concerned about their life time.
their factory now looks more clean and organized, than 5 years ago. They have to do for the names on their place: LG and Philips logo is on them
there is one more thing to say about new production: after observing the Shuguang factory here, it seems, the chinese learned, to improve their tubes.
after manufacturing firecrackers in glass housing for decades they got more knowledge and help from abroad to make thingss better. as this continues, they will understand, this can earn money by relaibility and quality. Some of their tubes are really good, as for example the KT66 and the newer EL34B edition. their small signal tubes perform well, but i am still concerned about their life time.
their factory now looks more clean and organized, than 5 years ago. They have to do for the names on their place: LG and Philips logo is on them
The EL34 branding seems to be better controlled than the choatic 6550 versions. SOme are downright dreadful performers. It does surprise me how versatile the EL34's are to being punished, the anode dissip ratings holding up better than other power tubes of the same power class..How the many different versions hold up on actual distortion and loading conditions is another question. This is an area I am interested in.
The 6550WE now an obsolete clear glass + pellet getter, is really a hopeless power performer, and yet it is the only 6550 version (apart from the orig NOS A GE series) which gives very low distortion. A pity that over 30W, the WE power handling ability crumbles.
A bit more expensive, my choice option for poke, is go for the EH KT90 (and not KT88). (another thread).This straight pencil tube amazed me beyond expectations. There are caveats; not all types of output transformer relationships for a given A-A impedance are a perfect match for all tubes as per quoted spec claims.
I've lost track if the EH KT90 is a real pentode modified from the line sweep TV version or if it is a beam tetrode. To me the new version looks like the latter.
richy
richy
The 6550WE now an obsolete clear glass + pellet getter, is really a hopeless power performer, and yet it is the only 6550 version (apart from the orig NOS A GE series) which gives very low distortion. A pity that over 30W, the WE power handling ability crumbles.
A bit more expensive, my choice option for poke, is go for the EH KT90 (and not KT88). (another thread).This straight pencil tube amazed me beyond expectations. There are caveats; not all types of output transformer relationships for a given A-A impedance are a perfect match for all tubes as per quoted spec claims.
I've lost track if the EH KT90 is a real pentode modified from the line sweep TV version or if it is a beam tetrode. To me the new version looks like the latter.
richy
richy
normally the KT90 should be a beam tetrode as the "K" tells you. it was "invented" by the Ei company from aTV tube to be an audio tube. and its not very linear. some of the KT88 or 6550 are the same, either penthodes or tetrodes bcc. same rating. RFT for example rated the EL34 as KT77 bcc. same or similar ratings. rebranding, renaming is a big business, iven if its not the accurate same thing. note: the KT77 was designed for higher G2 voltages in UL operation.
nowadays, they are so nice, to tell us, that a 2CX250 or so is an audio tube, which is in fact an RF power tube ( Svetlana ), seems, they wanna get rid of old stuff or, wanna foolish people. these tubes are not nice linear for audio, producing lots of harmonics, which were removed in RF low pass filters. making money is everything!
the 6550 is the answer to the KT88: pentode against beam tetrode. both have bee developed for public address ( VOLUME!! ) but not for hifi. same applies for EL84, cheap and loud enough for home radios. it was never claimed to be HiFi, at least in SE configuration. but i must say: some distortion adds to the sound, even order... why most manufacturers publish THD and never intermodulation? bcc.: its so bad. who is listening to one signal ( 1KHz) only? me not.
nowadays, they are so nice, to tell us, that a 2CX250 or so is an audio tube, which is in fact an RF power tube ( Svetlana ), seems, they wanna get rid of old stuff or, wanna foolish people. these tubes are not nice linear for audio, producing lots of harmonics, which were removed in RF low pass filters. making money is everything!
the 6550 is the answer to the KT88: pentode against beam tetrode. both have bee developed for public address ( VOLUME!! ) but not for hifi. same applies for EL84, cheap and loud enough for home radios. it was never claimed to be HiFi, at least in SE configuration. but i must say: some distortion adds to the sound, even order... why most manufacturers publish THD and never intermodulation? bcc.: its so bad. who is listening to one signal ( 1KHz) only? me not.
this is the reply I have just received from JJ Electronic
"we have never printed JJ tubes with another brand."
Best regards,
Julia Jurcova
sales
JJ Electronic
A. HLinku 4
ZIP: 022 01
Cadca, Slovak Republic
tel.: +421 41 4304 120
fax.: +421 41 4335 370
info@jj-electronic.com
JJ-Electronic - Vacuum tubes, Capacitors, Amplifiers - Home
"we have never printed JJ tubes with another brand."
Best regards,
Julia Jurcova
sales
JJ Electronic
A. HLinku 4
ZIP: 022 01
Cadca, Slovak Republic
tel.: +421 41 4304 120
fax.: +421 41 4335 370
info@jj-electronic.com
JJ-Electronic - Vacuum tubes, Capacitors, Amplifiers - Home
Which obviously points towards older Tesla sourced tubes,not a bad thing afterall.
Hello, I need opinions please...
Local ML sell these EL-34 (4 and matched) for the same money it costs me to replace one (single) KT-88 Prima Luna "original" .....
I consulted the seller if they EL34L or new EL34II, but not clarified the point ...
What do you think, they can be faked ?
Thank you !
Sorry my english !
Local ML sell these EL-34 (4 and matched) for the same money it costs me to replace one (single) KT-88 Prima Luna "original" .....
I consulted the seller if they EL34L or new EL34II, but not clarified the point ...
What do you think, they can be faked ?
Thank you !
Sorry my english !
Attachments
Hi Peter !
Thanks for your advice, then I buy these four here and I'll see you get a KT-88 Prima Luna to replace the failed.
I did not expect to fail so soon, has approximately 500 hours of use ....
A friend will come to Germany soon, do not know where I could buy in Europe?
Thanks again !
Thanks for your advice, then I buy these four here and I'll see you get a KT-88 Prima Luna to replace the failed.
I did not expect to fail so soon, has approximately 500 hours of use ....
A friend will come to Germany soon, do not know where I could buy in Europe?
Thanks again !
Attachments
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Hi Peter !
Thanks for your advice, then I buy these four here and I'll see you get a KT-88 Prima Luna to replace the failed.
I did not expect to fail so soon, has approximately 500 hours of use ....
A friend will come to Germany soon, do not know where I could buy in Europe?
Thanks again !
http://www.tube-town.net/
Hi Peter !
Thanks for your advice, then I buy these four here and I'll see you get a KT-88 Prima Luna to replace the failed.
I did not expect to fail so soon, has approximately 500 hours of use ....
A friend will come to Germany soon, do not know where I could buy in Europe?
Thanks again !
Never heard of prima Luna, but the KT88 in the picture looks like a standard Chinese KT88?
Yes, they are provided Shuguang tubes "selected",
and have acquired a machine to stamp his mark...Attachments
At this moment they are already running the new four EL-34 tubes brand JJ Electronics - ex Tesla- in my amplifier.
They work perfectly, and have been paired, it says on the label.
Screen printing has been hidden, Prima Luna sockets are backwards .....? or is a commercial mischief to buy tubes prints for them ?
Because after reading this article I know you do not think...
http://www.jacmusic.com/nos/images/Fakes/
Reviews ?
They work perfectly, and have been paired, it says on the label.
Screen printing has been hidden, Prima Luna sockets are backwards .....? or is a commercial mischief to buy tubes prints for them ?
Because after reading this article I know you do not think...
http://www.jacmusic.com/nos/images/Fakes/
Reviews ?
Attachments
Last edited:
Thanks to fake tube craze is wise to choose brands who make tubes today, so JJ is a good choice. Buying "NOS" is very risky unless one knows the seller personally. For example, I found some old-timers repair man with some genuine little NOS stocks, but most of time they have TV tubes and most uncommon ones. Since I are a DIY addict, I collect these tubes if price is fair.
Apex maybe is a tube vendor/re-seller who measures their tubes for matching. Is good, if honestity is involved here. I believe some sellers actually will made this matching process.
About Prima Luna tubes: Is more-or-less common for some makers/vendors, like some guitar and Hi-Fi amplifiers makers, to put "custom brand" printed tubes, and most of time is almost "reject" from production I suppose, since I found more defects statistically in "proprietary brands" tubes in amps I repair for friends (maybe only my bad luck, but...). Exceptions always exists, of course.
So I suppose these PrimaLuna tubes to be not fakes per se, but only those undesirable results in modern tube business...
Apex maybe is a tube vendor/re-seller who measures their tubes for matching. Is good, if honestity is involved here. I believe some sellers actually will made this matching process.
About Prima Luna tubes: Is more-or-less common for some makers/vendors, like some guitar and Hi-Fi amplifiers makers, to put "custom brand" printed tubes, and most of time is almost "reject" from production I suppose, since I found more defects statistically in "proprietary brands" tubes in amps I repair for friends (maybe only my bad luck, but...). Exceptions always exists, of course.
So I suppose these PrimaLuna tubes to be not fakes per se, but only those undesirable results in modern tube business...
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Thanks for your interest in the article. Prima Luna says that source Shuguang, and the tubes are tested by them and are only marked with the logo if they are within certain parameters. Others are returned .... and if I think I have not been lucky. Anyway, for the price of one KT-88 I bought a house two tubes Sovtek musical instruments and rockers boys are not deprived of punishing, they should be better Russian than the Chinese ..... talking about valves course....
Thanks friend, unfortunately in my country that mark is not achieved, we usually have to settle for what is offered in Mercado Libre, which comes to our South American E-Bay.
Valvulas Electronicas en MercadoLibre Argentina[A:valvulas-electronicas,B:2]
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