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    Now we have three types of KT120 tubes (really two) - photo ..

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    Bob Latino
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    Now we have three types of KT120 tubes (really two) - photo ..

    Post by Bob Latino on Thu Nov 28, 2013 8:37 pm

    Shuguang in China now makes a KT120 output tube that appears to be slightly different than the original Tung-Sol KT120. Psvane also has a KT120 out but it appears to me to be a rebadged Tung-Sol KT120.

    Link > Psvane KT120

    Chinese KT120 photo below



    All of these would be suitable in a VTA ST-120 or VTA M-125 monoblock. If anyone picks up a quad of the Shuguang KT120's and trys them out, please comment here in this thread on their sound? I think that Shuguang picking up the manuafacture of their own KT120 is good because competition will keep pricing stable on the KT120.

    Bob

    ValleySounds

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by ValleySounds on Fri Nov 29, 2013 9:35 pm

    I was looking at the Psvane kt-120's. They do look like rebranded Tung sols but they are missing the side getter. They may be different but I cant find any info on the net. The Shuguang looks like it may be worth a shot.

    No side getter


    tung sol


    Last edited by ValleySounds on Fri Nov 29, 2013 9:44 pm; edited 1 time in total (Reason for editing : added a pic of the tung sol)
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    sKiZo

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by sKiZo on Sat Nov 30, 2013 12:17 am

    I imagine the Psvane's are made by Shuguang. That's the deal they had on the KT88's. Only difference was the branding and according to Grant, they got the pick of the barrel, selecting only a small percentage of the supply for their product line.

    Not sure how much truth there is to all that, but I do love my KT88's ...



    (But not as much as the TungSol KT120's ... those are breaking in real nice!)

    chefothefuture

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by chefothefuture on Sun Apr 08, 2018 12:06 pm

    Well, reviving a zombie thread, I just purchased a set of the Psvane Treasure KT120-Z CB and have been having nothing but problems with them in two different VTA ST120s w/octal driver boards, built to spec. At this point, the tubes can not be biased to .50v with out excessive hum and after about 30 seconds, pops and crackles. (Only done once, power removed immediately). With a GZ34 rectifier, they run quiet(ish) at a bias of .25v. I can't use a GZ37 with them at all. The only information I can get from Grant Fidelity is that they are made to the specs of the Tung Sol, but the factory has not produced any data sheet and given that the tubes do not function properly in two VTA ST120s that are fine with Tung Sols, this is certainly not true. I must say that for the expense, so far the Psvane KT120-Z CB's are a huge fail. Not recommended at all.
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    sKiZo

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by sKiZo on Sun Apr 08, 2018 5:38 pm

    Just to clarify, you HAVE used the TungSol KT120's in the same amp that the Psvane tubes fail in?

    chefothefuture

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by chefothefuture on Sun Apr 08, 2018 6:27 pm

    sKiZo wrote:Just to clarify, you HAVE used the TungSol KT120's in the same amp that the Psvane tubes fail in?

    Yessir. Actually tried them in two different VTA ST120s where the Tung Sol’s are fine and the Psvane’s are not.
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    sKiZo

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by sKiZo on Sun Apr 08, 2018 8:00 pm

    Good to know! Been thinking of picking up a backup set as mine are getting abit long in the tooth, and I may avoid those until I see a better track record ...

    FYI - I had similar issues with one in a quad of Psvane KT88's where it refused to bias up properly. I could get it to go up to spec, but it'd fade fast.
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    Kentley

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by Kentley on Sun Apr 08, 2018 8:43 pm

    Velly interestink!
    I have bought 7 Chinese tubes. One was crap. That record's not so bad, but it could be better. Fortunately the 6 good one are fantastic, and lasting nicely.
    Here's my prediction, based on recent history:
    Remember in the 1950s and Sixties when "Made in Japan" was a guarantee that you'd better watch out? Look at 'em now. This is a natural evolution of technology which we see unfolding. In ten years, I predict that "Made in China" will be a sure sign of quality.
    Call me a fuel. Probably gas.

    chefothefuture

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by chefothefuture on Sun Apr 08, 2018 11:02 pm

    Well, after trying changing some resistors, I’m still getting noise and am not able to bias properly. Add to that one tube will not “light up” from cold unless tapped with a pencil. Total fail. Grant Fidelity tells me I’d be subject to a restocking fee. (Insert explicate language here!!!) So, they basically don’t provide information for me to even know if the bloody things are compatible, (“Oh they’re the same spec as Tung Sols’”) but they now say I’m subject to a fee, even though the things are defective or junk. They say they need to be in “as new” condition when they arrived with marks and discoloration on the key ways. So not only can I not recommend the Psvane KT120, but I can also say, stay away from Grant Fidelity. Caveat emptor!
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    cci1492

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by cci1492 on Mon Apr 09, 2018 6:48 am

    Kentley wrote:Velly interestink!
    I have bought 7 Chinese tubes. One was crap. That record's not so bad, but it could be better. Fortunately the 6 good one are fantastic, and lasting nicely.
    Here's my prediction, based on recent history:
    Remember in the 1950s and Sixties when "Made in Japan" was a guarantee that you'd better watch out? Look at 'em now. This is a natural evolution of technology which we see unfolding. In ten years, I predict that "Made in China" will be a sure sign of quality.
    Call me a fuel. Probably gas.

    When they plant the Chinese flag on the moon, prices will go up!
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    skriefal

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by skriefal on Mon Apr 09, 2018 7:54 am

    cci1492 wrote:
    When they plant the Chinese flag on the moon, prices will go up!

    That has effectively already happened.

    http://www.businessinsider.com/china-flag-on-moon-2013-12
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    cci1492

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by cci1492 on Mon Apr 09, 2018 8:17 am

    Ground control to major Tong! I'd better run to Harbor Freight and get that OBD2 reader I've been eying!
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    jfine

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by jfine on Mon Apr 09, 2018 5:45 pm

    deepee99 wrote:. . . and acquired a slightly used quad of British GEC KT-88s for the Sachs-modded VTA ST-120 from Andy Bowman. No comparison to the modern stuff. They convey layers of bass and treble detail I've never heard before. And they'll likely outlive me.

    Damn you, the GL KT88's are really the only new production tubes I use, only because I need 8 for the M125's, and don't exactly feel like dropping $$$ on something better, but if/when the auto biased boards are ready for the M125, I may change my mind.


    Last edited by jfine on Mon Apr 09, 2018 5:47 pm; edited 1 time in total
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    jfine

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

    Post by jfine on Mon Apr 09, 2018 5:47 pm

    And BTW, I'm all done with chinese tubes except in a pinch maybe the 5AR4.

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    Re: Now we have three types of KT120 tubes (really two) - photo ..

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