Shuguang Black Treasure 6CA7 and Psvane 6CA7-TII

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I searched the internet and could find no datasheets for either tube. That is really strange but I do like the EH big bottle 6CA7 and I noticed that the Z version is a big bottle and is not refereed to as a EL34 however the TII you mentioned is [6CA7/EL34].
As far as sound difference to me a EL34 is midrange and detailed but lacks both Bass and upper highs. The EH 6CA7 solid from top to bottom and Just a great sounding tube. Just my 2 cents.

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To know for sure about any brand of 6CA7 you must check the data sheet for that exact tube and brand. The EH is a tetrode the Sevtlana EL34/6CA7 is a pentode. Unfortunately without the data sheets on the  2 that you are looking at it is impossible to know. However if they list the 2 together I would suspect pentode. As in EL34/6CA7 as listed on the Psvane 6CA7/EL34-TII. The EH is modeled after the Phillips Big Bottle 6CA7 tetrode and sounds nothing like a EL34. The JJ 6CA7 is also a pentode.
http://www.thetubestore.com/lib/thetubestore/JJ-6CA7.pdf
http://www.drtube.com/datasheets/el34-sed2002.pdf
http://www.ehx.com/products/6ca7

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sailor wrote:To know for sure about any brand of 6CA7 you must check the data sheet for that exact tube and brand. The EH is a tetrode the Sevtlana EL34/6CA7 is a pentode. Unfortunately without the data sheets on the  2 that you are looking at it is impossible to know. However if they list the 2 together I would suspect pentode. As in EL34/6CA7 as listed on the Psvane 6CA7/EL34-TII. The EH is modeled after the Phillips Big Bottle 6CA7 tetrode and sounds nothing like a EL34. The JJ 6CA7 is also a pentode.
http://www.thetubestore.com/lib/thetubestore/JJ-6CA7.pdf
http://www.drtube.com/datasheets/el34-sed2002.pdf
http://www.ehx.com/products/6ca7

I have reason to think that JJ 6CA7 is a beam tetrode.( as the tube description says)
I will know for shure when my contact has answered.

Check the above link to the JJ 6CA7 data sheet. It is listed and pictured as a pentode.

sailor wrote:Check the above link to the JJ 6CA7 data sheet. It is listed and pictured as a pentode.

Yes i know. That sheet is in error ( i guess it's a language issue). If you look at the sheet
for 6550 they call it "beam-pentode" !

The crucial thing is if they have A: a third grid or B: beam forming plates.
As i can see without breaking one is (B).

In the old days the El34 was a 6CA7, IE: European versus American designation. My Mullards say they are both. So anyone can produce a pentode and justifiable call it a 6Ca7. The only thing I can see that would make it a pintode is if pin 1 is connected to grid 3 as pictured [JJ].
All I know is I can't find a data sheet that shows an internal diagram or pin out for either the EH or the Phillips big bottle. As far as JJ goes, I am glad they are in the tube business but you are right about the fact you can't always trust what the say or claim. After all they claim they produce a 12AX7 that is a copy of the venerable Telefunken but there designs have nothing in common with each other. JJ short plate Big T. long plate. EI on the other had did make exact copies just not as good a quality control because they bought Telefunkens tube making equipment.
All I know for sure is the EH big bottle are great sounding tubes and that is compared to NOS EL34 Mullards. However if midrange detail is your thing with rolled off bass and highs then the EL34 the way to go. I have never owned or heard the big bottle JJ so I can't comment.

sailor wrote:In the old days the El34 was a 6CA7, IE: European versus American designation. My Mullards say they are both. So anyone can produce a pentode and justifiable call it a 6Ca7. The only thing I can see that would make it a pintode is if pin 1 is connected to grid 3 as pictured [JJ].  
All I know is I can't find a data sheet that shows an internal diagram or pin out for either the EH or the Phillips big bottle. As far as JJ goes, I am glad they are in the tube business but you are right about the fact you can't always trust what the say or claim. After all they claim they produce a 12AX7 that is a copy of the venerable Telefunken but there designs have nothing in common with each other. JJ short plate Big T. long plate. EI on the other had did make exact copies just not as good a quality control because they bought Telefunkens tube making equipment.
All I know for sure is the EH big bottle are great sounding tubes and that is compared to NOS EL34 Mullards. However if midrange detail is your thing with rolled off bass and highs then the EL34 the way to go.  I have never owned or heard the big bottle JJ so I can't comment.

I will dissect an JJ-6CA7 in due time and report back(if anyone is interested)
As for ECC83, JJ makes short-plates ( ECC83S ) and long-plates ( ECC803 ) and in addition
the also make ECC83MG that is resold by "new telefunken" http://www.telefunken-elektroakustik.com/products/tubes/black-diamond-tubes/ecc83-tk.php

The ECC803 ( long-plates ) is said to be very resistant against micro-phony and is preferred in
guitar amps here. ECC83S sounds fine in my PAS3X, in fact comparable against the original
"dynaco"-marked originals.

I know what JJ claims about there 12AX7/ECC83 but I know for a fact that the standard T. was a long plate and the ECC803 was a short plate. I have also heard both and the JJ falls very short of a true T. JJ has no sparkle in the highs that is the signature of a true T. I am not a crazy old tube freak but I used nothing but T. 12AX7 in my modified PAS3 preamps all through the 70's and 80's and have that sound permanently embedded in my brain. I use JJ and other ECC83 now because the NOS Telefunkens are now to rare and expensive. They were about $3 when I used them. Again I may sound like I am knocking JJ I am not. They are not doing anything different than any other manufacture. They all claim they are making exact copies of old tubes. Really. A Good example, look at any old EL84 and compare it to a new tube and tell me they are an exact copy. If you can't see the difference, well.
Sorry for the comments but the Telefunken 12AX7/ECC83 is a real sore spot for me. I wish someone would actually make a true exact copy.

Back to the original question, I got some of the Shuguang Black Treasure 6CA7 tubes from Grant Audio for my Yaquin MC-30L amplifier before I built my ST-120.  They certainly sound nice but I don't think they were that superior to the regular Shuguang blue-bottle 6CA7 tubes that came with the amplifier.  In retrospect, I think I should have saved the money.  That said, I rotate the Yaquin and the ST-120 once in a while and the Yaquin with the Black Treasures is very close to the ST-120 with KT-120 tubes.  I have no idea if it is a beam tetrode or a pentode tube.

Thanks for the input on the Shuguang Black Treasure ......an how about the Yaquin...I like there setup an $$...so you fell there close to the ST120s....Cool smll  output tubes....holing it own with the KT120.....all good two know............jj never work for me...have fun with tubes... hoho




Thanks for the site Bob...................................

JJ 6CA7 seems to be beam-tetrodes, see
http://www.marshallforum.com/workbench/21555-jj-6ca7-power-tubes.html#post263740

I still wait for a broken one to disassemble.