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    ST-120 tube help

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    Leigh W

    Posts : 45
    Join date : 2013-04-02

    ST-120 tube help

    Post by Leigh W on Tue Apr 02, 2013 9:07 pm

    Hello everyone. This is my first post here and I have a tube question if I may. My new ST-120 kit should be here in a couple of days and I will be ordering a set of KT88 tubes very soon. I have looked through many pages on the forum and have found some questions/answers regarding tube rolling but nothing specific as to what brands seem to sound the nicest and which ones seem to self destruct at an early age. I know what the ear perceives is highly personal but was wondering if one brand or another is favored (stands out!) by most users of the ST-120. At the moment I am leaning towards the Shuguang KT88's just from what I've read about reliability and sound quality. The others I'm considering are the JJ's, Electro Harmonix and the Sovtek's. I had a tube amp a few years ago running the Sovtek EL34's and I didn't care for their sound quality or their life span, so am a bit skeptical of the Sovtek's yet have heard good things about them in KT88 form. I will be running 3 Electro Harmonix 12AU7's in the driver stage because I already have them. Are these a good choice? Any comments on what seems to give the nicest highs, mids and solid bass would be appreciated for the driver tubes. I will be running the Shuguang rectifier tube as well. I've read the Gold Lions are a Superior sounding tube but I've read in a few forums that they have a tendency to not last very long. Sorry for the "long winded" post but as an audiophile I would like to start with the nicest sounding/lasting tubes I can find for a reasonable cost. I am using the Transcendent Sound grounded grid as a preamp and stream music via flac from my computer. I also use a Marantz SA8004 sacd player as a source among others. Speakers are Klipsch RF-82's (98db). I listen to Jazz, classical and light rock mostly. Thanks for your input and time...Cheers! Leigh

    ArlanB

    Posts : 52
    Join date : 2011-01-23
    Age : 69
    Location : Santa Cruz, California

    ST 120 Help

    Post by ArlanB on Wed Apr 03, 2013 2:31 am

    Leigh,

    I have had my ST 120 for almost 5 years now and have gone through JJ, Elektroharmonics, Gold Lion, and Penta Labs KT88s. I am at present using the Penta Labs KT88SC from Daves Tubes. They work very well in the 120, have excellent sound and a respectable tube life. They are almost two years old now and still going strong. JJ died after about 9 months, Elektroharmonics lasted almost 8 months, and the Gold Lions died within two weeks. All sounded good but after using tubes made in Russia and elsewhere in that general area, I decided to try Shuguang manufactured tubesand have not been disapointed. The Penta Labs are manufactured by Shuguang to Penta Labs specs and they do sound good and to their credit have lasted the longest.

    ArlanB

    peterh

    Posts : 642
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: ST-120 tube help

    Post by peterh on Wed Apr 03, 2013 3:10 am

    Leigh W wrote:Hello everyone. This is my first post here and I have a tube question if I may. My new ST-120 kit should be here in a couple of days and I will be ordering a set of KT88 tubes very soon. I have looked through many pages on the forum and have found some questions/answers regarding tube rolling but nothing specific as to what brands seem to sound the nicest and which ones seem to self destruct at an early age. I know what the ear perceives is highly personal but was wondering if one brand or another is favored (stands out!) by most users of the ST-120. At the moment I am leaning towards the Shuguang KT88's just from what I've read about reliability and sound quality. The others I'm considering are the JJ's, Electro Harmonix and the Sovtek's. I had a tube amp a few years ago running the Sovtek EL34's and I didn't care for their sound quality or their life span, so am a bit skeptical of the Sovtek's yet have heard good things about them in KT88 form. I will be running 3 Electro Harmonix 12AU7's in the driver stage because I already have them. Are these a good choice? Any comments on what seems to give the nicest highs, mids and solid bass would be appreciated for the driver tubes. I will be running the Shuguang rectifier tube as well. I've read the Gold Lions are a Superior sounding tube but I've read in a few forums that they have a tendency to not last very long. Sorry for the "long winded" post but as an audiophile I would like to start with the nicest sounding/lasting tubes I can find for a reasonable cost. I am using the Transcendent Sound grounded grid as a preamp and stream music via flac from my computer. I also use a Marantz SA8004 sacd player as a source among others. Speakers are Klipsch RF-82's (98db). I listen to Jazz, classical and light rock mostly. Thanks for your input and time...Cheers! Leigh

    I am very pleased with JJ kt-88 ( is i am with JJ 6550)
    As drivers i use JJ ECC82 which was a huge difference from GE 5963 (which i consider next to dull)

    sKiZo

    Posts : 1285
    Join date : 2013-04-01
    Location : Michigan USA

    Re: ST-120 tube help

    Post by sKiZo on Wed Apr 03, 2013 3:43 pm

    Gotcha beat ... this is my THIRD post ...

    Newbie here too ... just ordered an ST-120 kit - so I can't give you any specifics on longevity or smiles per miles, but I did a whole lot of reading and head scratching concerning tube selection.

    My final selection ...

    - A matched quad of TungSol KT-120's. Those get good reviews in the ST-120 amp and are usually described as warm sounding with a tight bottom. Maybe a bit less boom than a lot of tubes. I'm going more for the "bulletproof" aspect ... they haven't really been around long enough to have much of a track record, but they're made to work a lot harder than what this amp calls for. Consensus seems to be, load them up for 55ma and let em rip.

    - RCA clear top with a Telefunken center for the drivers. Hoping for the best on those.

    - The rectifier gave me problems, what with the raging debate about bottles vs solid state AND the big output tubes. I understand you do get some power drop running a bottle, but the solid state versions have discernible switching noise. My solution - one of each. I got a couple Shuguang KZ34's AND a Copper Cap WS68 coming so I can settle it for myself. I also found a real nice Amperex (Blackburn Mullard rebrand) for special occasions, but I'll be sure to burn the amp in real good before plugging that in.


    Leigh W

    Posts : 45
    Join date : 2013-04-02

    ST-120 tube help

    Post by Leigh W on Wed Apr 03, 2013 8:34 pm

    Thanks to all of you for the input on tube selection. I am definitely leaning towards the Shuguang KT88's as per my reading and as per ArlanB, Thanks for covering the many brands you have used and what seems to work well and last the longest. I have JJ12AT7's in the driver stage of my Transcendent Sound OTL and love the detail and sound stage they produce over the Jan Phillips. The Jans are nice but not quite as detailed in my opinion as the JJ's. I think I will purchase a set of the JJ's for the ST-120 and see how they sound after break in compared to the Electro-Harmonix I originally planned to use.

    Skizo. Thanks for the input on what you have read about the different tubes. I was thinking about running the TungSol KT-120's as well just because of the extra load they can withstand. I asked Bob which he thought sounded the nicest and he told me he seemed to feel that the KT-88's were best suited to the ST-120. Why? I don't know. as he didn't say why. I guess it's because the circuit was designed around the KT-88. Just thought I would pass on that bit of information too further confuse us. Haha, just kidding! My kit should arrive tomorrow and am looking forward to the build. Thanks too all and cheers!...Leigh

    corndog71

    Posts : 444
    Join date : 2013-03-19
    Location : It can get windy here

    Re: ST-120 tube help

    Post by corndog71 on Wed Apr 17, 2013 12:17 pm

    I've enjoyed Valve Art EL34s in my ST70 and MkIV amps as well as their EL84s in my ST35. They're chinese but have held up better than the EH, Sovtek, and even some winged C and Svetlanas. They're cheap but sound pretty good. The Valve Art EL84s were just a step down from the new Genalex I'm currently running.

    I've changed my mind about building the M-125s and have decided to build a ST-120. I've been wanting a KT88 amp for a while now and am almost ready to pull the trigger.

    Andy Jersey

    Posts : 69
    Join date : 2012-09-29

    Re: ST-120 tube help

    Post by Andy Jersey on Fri Apr 19, 2013 7:23 pm

    Can't go wrong with KT-120s. Driver board tubes influence sound more than output tubes. I would hold of on tube rolling for 6 months. PIOs take a long time to breakin. Probably other parts too, maybe not as long. If you experiment early on, you'll be chasing a moving target. My 2c

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: ST-120 tube help

    Post by WntrMute2 on Sat Apr 20, 2013 10:21 am

    My experience with output tubes in my ST-120 doesn't match what others experience. My original Sovteks sounded fine but one decided to white plate after a year or so. I ordered a set of Penta Lab Kt-88s and while waiting for them to show up, I put the Sovteks back in after Slowly bringing the bias back up. The sounded fine and I kept them in for a couple of additional weeks. I then purchased a set of Tung-Sol Kt-120s for backup. They sounded close to the Penta Lab tubes, maybe a little fuller in the bass. No real noticeable deficiencies, but not as delicate as some of the 88s. After one of the Pentas cooked off, I lived with the Tung-Sols for a while happily. I finally purchased a set of Shuggie Black Treasure Kt-88s from a well respected seller in Hong-Kong. He offers free shipping and a year warrantee! Arrived in a weeks time and I have been very satisfied with the sound. Probably buy from him again when the time comes.
    Black Treasures

    Andy Jersey

    Posts : 69
    Join date : 2012-09-29

    Re: ST-120 tube help

    Post by Andy Jersey on Sat Apr 20, 2013 10:47 am

    lol my wife came down while reading your post and asked if I was going goth. If you have issues with these let me know. Maybe i'll give them a shot when the time comes. How would you say they sound compared to the KT 120s?

    WntrMute2

    Posts : 96
    Join date : 2010-11-21

    Re: ST-120 tube help

    Post by WntrMute2 on Sat Apr 20, 2013 12:50 pm

    Just a bit more refined. A little tighter bass mostly. I should change that avatar, it is a picture of Molly Millions from the William Gibson series Neuromancer

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