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    VTA-120 For Dummies

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    matallan

    Posts : 12
    Join date : 2016-11-30

    VTA-120 For Dummies

    Post by matallan on Wed Apr 25, 2018 11:23 am

    I now have about 300 hours on my VTA-120 which I purchased from Bob Latino at tubes4hifi, and thought I would share my build experience. It may even help anyone who is unsure or undecided if they can build one of these kits.
     The kit arrives complete, organized and well packaged. Parts are all contained in their own  bag and are clearly labelled. For me, the best part was the assembly manual. It was as if Bob had written it especially for me. Simple step by step procedures, special warnings and check points along the way. Instructions are in a non technical form and are easy for a novice like myself to understand and follow. They also include a color photo and wiring diagram to compare and use as a guide. Full Disclosure!   I did email Bob a couple of times with questions that were too stupid or embarrasing to ask on a public forum. He always answered quickly and was more than helpful.
     I purchased a soldering iron,solder, a bag of cheap resistors, a few small hand tools and a couple blank PCB boards to practice soldering and then started my build.
     My original plan was to build the amp exactly as instructed and then with my new gained knowledge, perhaps build a custom unit as some of the more advanced builders have done, but after searching through the forums, I was confident that I could make a few changes with the info I had found.
     I had some aluminum plate lying around so I made a front panel and a plate to cover the main board. I also moved the power switch to the front, inputs to the rear, added a fused IEC power inlet, re located the bias test jacks and made the speaker terminals standard spacing.
     Aside from a few brain fade moments, assembly went quite smoothly. After checking and rechecking and then checking all instructions and wiring again,it was now time for initial startup.
     This was the part that had me concerned the most,as I do not have any troubleshooting experience and the fact that I made a few modifications which could potentially lead to some problems.
      Again, following Bobs printed instructions the start up procedure and all voltage tests were absolutely uneventful. It just works. Kind of anti-climatic!
      I have been using my amp for about four months with no issues what so ever.
     Not only is this a fun kit to build,I think it also a great way to start in this hobby and gain experience and knowledge about tube amplifiers. If you are a hands on person and can follow instructions, I think that you should have no problems building and enjoying any one of the tubes4hifi kits.





    [url=https://servimg.com/view/19893976/8]
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    corndog71

    Posts : 661
    Join date : 2013-03-19
    Location : It can get windy here

    Re: VTA-120 For Dummies

    Post by corndog71 on Wed Apr 25, 2018 11:38 am

    Looks great! Where did you get that power button?

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Wed Apr 25, 2018 12:14 pm

    corndog71 wrote:Looks great!  Where did you get that power button?
     It actually came from aliexpress. 19mm 10 amp
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    Dave_in_Va

    Posts : 232
    Join date : 2013-04-02

    Re: VTA-120 For Dummies

    Post by Dave_in_Va on Wed Apr 25, 2018 1:06 pm

    Congrats. that looks really nice.

    jasn54

    Posts : 39
    Join date : 2015-04-13

    Re: VTA-120 For Dummies

    Post by jasn54 on Wed Apr 25, 2018 4:56 pm

    Very nicely done mattalan. It gives me ideas about my own ST120...
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    wgallupe

    Posts : 124
    Join date : 2014-05-18
    Age : 64
    Location : Central Mass.

    Re: VTA-120 For Dummies

    Post by wgallupe on Wed Apr 25, 2018 5:32 pm

    Looks great! Well done.
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    pedrocols

    Posts : 113
    Join date : 2014-11-24
    Location : Western MA

    Re: VTA-120 For Dummies

    Post by pedrocols on Wed Apr 25, 2018 8:28 pm

    Nice build!

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Wed Apr 25, 2018 9:37 pm

    Thanks everyone for the kind comments. I think I am going to open it up and see if I can install the auto bias board. I kind of like the idea of setting the bias manually but it appears the auto bias board has many other advantages.
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    cci1492

    Posts : 188
    Join date : 2016-05-09
    Age : 57
    Location : Bergen County NJ

    Re: VTA-120 For Dummies

    Post by cci1492 on Thu Apr 26, 2018 9:43 am

    Clean and neat, very nice work!

    jasn54

    Posts : 39
    Join date : 2015-04-13

    Re: VTA-120 For Dummies

    Post by jasn54 on Thu Apr 26, 2018 1:31 pm

    I like the speaker leads too (same as mine).

    Dogstar

    Posts : 340
    Join date : 2014-06-23

    Re: VTA-120 For Dummies

    Post by Dogstar on Thu Apr 26, 2018 9:48 pm

    Nice looking build ...are those Edcor transformers or the VTA ST-120 transformers painted to look like Edcors?
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    Bob Latino
    Admin

    Posts : 2673
    Join date : 2008-11-26
    Location : Massachusetts

    Re: VTA-120 For Dummies

    Post by Bob Latino on Fri Apr 27, 2018 7:49 am

    Dogstar wrote:Nice looking build ...are those Edcor transformers or the VTA ST-120 transformers painted to look like Edcors?

    Those are VTA transformers ..

    dandrews

    Posts : 2
    Join date : 2018-04-27

    Re: VTA-120 For Dummies

    Post by dandrews on Fri Apr 27, 2018 8:22 am

    Matallan,

    Your build is beautiful! I plan to purchase one of Bob's ST-120 kits within a few weeks - I hope mine turns out half as nicely as yours. If you don't mind, I have a few questions for you:

    1. What are the four little yellow jacks near the 12AU7 tubes? Are those the bias adjustment pots?
    2. The four little red jacks near each KT88 tube - are those RCA jacks to measure the bias?
    3. How do you like the sound?

    Thanks!

    Dave

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Fri Apr 27, 2018 8:48 am

    I had to goggle Edcor to know what you meant. When I was looking at various paint colors, my wife said she liked the blue. So, blue it is. I originally wanted Ferrari red or one of the hammertone finishes. I also took her to lunch. Also, when packages arrive or a large box of matched tubes arrive from Jim McShane, she just says COOL!  Every bit helps.

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Fri Apr 27, 2018 8:55 am

    dandrews wrote:Matallan,

         Your build is beautiful!  I plan to purchase one of Bob's ST-120 kits within a few weeks - I hope mine turns out half as nicely as yours.  If you don't mind, I have a few questions for you:

    1.  What are the four little yellow jacks near the 12AU7 tubes?  Are those the bias adjustment pots?
    2.  The four little red jacks near each KT88 tube - are those RCA jacks to measure the bias?
    3.  How do you like the sound?

    Thanks!

    Dave

    Yes 1 and 2 are correct. The sound is pretty good considering the way i have it hooked up. It is just an old phone with MP3 and a pair of Volt 6 or a pair of low end infinity speakers. I still need a preamp or Dac and new speakers.

    dandrews

    Posts : 2
    Join date : 2018-04-27

    Re: VTA-120 For Dummies

    Post by dandrews on Fri Apr 27, 2018 10:55 am

    Matallan,

    Thanks for the quick response. When you say Volt 6 speakers, I assume you're referring to the DIYSG co-axials? How do you like them? I want to build a pair of the Volt 10's at some point. I just finished building and veneering a set of DIYSG 1299's. I'm currently running them off a cheap Chinese EL34 SE tube amp (maybe 8 watts/channel tops), and they sound great.

    Dave

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Sat Apr 28, 2018 8:25 am

    dandrews wrote:Matallan,

        Thanks for the quick response.  When you say Volt 6 speakers, I assume you're referring to the DIYSG co-axials?  How do you like them?  I want to build a pair of the Volt 10's at some point.  I just finished building and veneering a set of DIYSG 1299's.  I'm currently running them off a cheap Chinese EL34 SE tube amp (maybe 8 watts/channel tops), and they sound great.

    Dave

    Yes DIYSG. They can be seen in the above photos on my workbench. They are sitting upside down and are the angled flat pack.They sound good, perhaps a little thin? For surrounds they would be perfect. I also built 2 15" ultimax subs with intentions of building the Fusion 8 but instead I will be purchasing new speakers this summer, as I don't have a shop anymore to build them in. Sold the subs and crown amps and will be looking for a more full range speaker.
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    crkohut

    Posts : 10
    Join date : 2016-11-02
    Age : 57
    Location : Sudbury, Ontario, Canada

    Re: VTA-120 For Dummies

    Post by crkohut on Thu May 17, 2018 3:47 pm

    Nice!! Very Happy
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    deepee99

    Posts : 1993
    Join date : 2012-05-23
    Location : Wallace, Idaho

    Re: VTA-120 For Dummies

    Post by deepee99 on Thu May 17, 2018 7:15 pm

    Very sweet. Looks like a pro built it!

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Thu May 17, 2018 10:05 pm

    crkohut wrote:Nice!! Very Happy

    Thanks. It was fun to build and I learned a lot in the process. Not sure what to build next.

    matallan

    Posts : 12
    Join date : 2016-11-30

    Re: VTA-120 For Dummies

    Post by matallan on Thu May 17, 2018 10:11 pm

    deepee99 wrote:Very sweet. Looks like a pro built it!

    Haha Far from a pro. I actually went through these entire forums and got ideas and extra info to make some of the changes safely and correctly.

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