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    Tung Sol KT-120 's



    Posts : 304
    Join date : 2010-02-03
    Location : Costa Rica

    Tung Sol KT-120 's

    Post by baddog1946 on Thu Jun 03, 2010 8:14 pm

    Weren't you using the 120's in your own amp recently for a while? I think that the longevity factor alone makes them at least a viable purchase at such a reasonable price and they would be impervious to any voltage wear and other wear factors the ST-120 would throw at them.
    You said they sounded more or less like the KT-88's. At that price you would be buying a set of heavy duty tubes that are similar in sound and price as the Gold Lions.
    I ordered a pair to see what's is up with them and will report my findings in due time.
    I am using Gold Lions in my ST-120 right now so I will have an opportunity to make a good A-B comparison.
    I don't need to squeak the last watt out of them. My ST-120 will blow up any one of my speakers as it is. I am currently using a set of Decware NFX's that I can only turn up to about 4-5 on my 'Bottlehead Foreplay III Extended". This amp already has big balls.
    But as an audiophile I like to play at my hobby and that's why we are all here on the forum exploring new ideas and gear. I think we all have a little mad scientist in us.
    I am also going to put one of those attenuator kits in my amp as soon as I have some more $$ and recover from the KT-120's purchase.
    What else should we audiophiles spend our mad money on booze?
    Me, I like tunes and stereo gear.Not to mention writing to fellow audiophiles on this forum.

    Bob Latino

    Posts : 2382
    Join date : 2008-11-26
    Location : Massachusetts

    Re: Tung Sol KT-120 's

    Post by Bob Latino on Fri Jun 04, 2010 5:03 pm


    I have gone back to the Genalex Gold Lion KT88's in my personal ST-120. I think the top end on the Gold Lion KT88's has a hair more extension at least in the ST-120 amp. The Tung-Sol KT120's sound a little "warmer" biased at bias settings for a KT88 and even a little higher (.750 VDC per tube or 75 milliamps). I didn't want to go up any higher than .750 VDC bias per tube in the ST-120. Although the power transformer in the ST-120 is rated at 425 milliamps, four KT120's biased at 75 milliamps = 300 milliamps just for the output tubes. I don't know how much current above the 300 milliamps the three 12AT7's and a GZ34 tube rectifier eat up. As I have mentioned on another post you will never get all of what these tubes can do in the ST-120 or any other KT88 based amp. I am thinking that the Tung-Sol KT120's will need 100 to 120 milliamps in order sound as they were designed to sound. I have a feeling they will sound less "tubey" and more linear at higher bias settings ...


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