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    Thanks Roy! VTA 70 board installed



    Posts : 1
    Join date : 2015-02-24

    Thanks Roy! VTA 70 board installed

    Post by yaleforks on Fri Apr 03, 2015 11:00 am

    So I had always wanted to get into tube audio but had been waiting until I found a great deal on an amp.

    I was at an auction house and noticed a ST-70 that was going up for sale.  While I was looking it over a member of the auction team approached me and told me about the amp.  The original board had been serviced and all caps replaced with a mix of Orange Drops and Dayton caps.  The selenium rectifier had been replaced, a set of xf2 Mullards and a f32 Mullard gz34 were on board, driver tubes were RCA black plate 7199s.  Also included in the auction were a Weber Copper Cap and 2 full quads of NOS Sylvania fat bottle 6CA7 outputs.

    So the auction starts and one of the last items was the amp.  I was worried as there was an obvious flipper in the crowd who was buying all the vintage audio up.  Once the amp went on the auction block I put in the first bid at 100 dollars and was surprised when nobody else put in a bid.  I later learned that the other audio guy had gone to the bathroom and missed bidding on the amp Laughing Laughing Laughing Laughing

    After the auction the team member who I spoke with told me that I got an amazing deal as the 2 Quads of 6CA7 alone are worth 5-6 hundred dollars.

    I took the amp home and biased it up and listened for a couple of hours.  While I liked the amp I thought it was a little laid back and sounded veiled, so off to the internet I went to look at mods when I found the tubes4hifi page.  I decided on the standard VTA board I was wary of changing out the cloth lead transformer for a newer one.  After a shipping mixup which Roy corrected immediately I had the board built with russian PIOs and a new quad cap installed.

    Right now I have 200 hours on the amp with the fat bottle Sylvania 6CA7s, RCA long black plate 12bh7s on the outside and a CBS-Hytron 5814 black plate in the center position.  I have never heard an amp so detailed in my life and it just keeps getting better and better!!

    Thanks Roy!!

    Up next will be a preamp build


    Posts : 1268
    Join date : 2008-11-30

    Re: Thanks Roy! VTA 70 board installed

    Post by tubes4hifi on Fri Apr 03, 2015 12:47 pm

    yes, wow, you got a steal on the amp and those Mullard tubes in good shape are worth around $100 each.
    Nice job on the new board install, and the amp looks great. Enjoy the music!!!!


    Posts : 308
    Join date : 2015-03-06
    Age : 64
    Location : Worcester, MA

    Re: Thanks Roy! VTA 70 board installed

    Post by Kentley on Fri Apr 03, 2015 1:24 pm

    Geez,some people have all the luck. I'm not above envy yet. rendeer

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