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    ST-70 alive again!

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    batman7349

    Posts : 14
    Join date : 2014-12-08

    ST-70 alive again!

    Post by batman7349 on Thu Jan 01, 2015 5:58 pm

    It's been a busy couple of weeks over the Christmas Holidays. Finally got my factory wired ST-70 tuned up and into operation. It all started this summer when I blew up the front channel speakers in my home theater. After looking at my options I decided to build a pair of GR Research X-LS Encores with Mills and Sonicaps. Wow they sounded pretty good so I built a matching center channel. Then I decided they sounded so good that I needed to uncover my collection of around 800 vinyls from the 60's through the 80's. Pulled out my old Technics SL-D33 and bought an RCA phono preamp to get started. Hmmmm not impressed. So I started surfing the cheap and cheerful site and decided to buy a Little Bear T10 RIAA stage and a three tube Guanzo preamp/buffer. Then I built a pair of TDA7297's with bigger caps. Only 5 watts but it really lit the flame. Now the hunt was on for a decent price on an ST-70. While traveling on business I walked into a man cave store in Belden, MO and low and behold he had a factory wired ST-70 sitting on the shelf. Done Deal. Got it home checked the wiring, replaced the selenium rectifier with a diode and swapped out the 7199's for a pair of 6GH8A's and brought it up on a dim bulb tester. Sounded good until I placed the Little Bear in line, buzz city. I did all the mods on the LB with NOS PIO caps, metal base, ground transformer, tube shield. Now we're buzz free. I built some oak cases to put the preamp and Little Bear in, and an oak case to hold the system and some LP's and fired it up. Sounds pretty damn fine to me! Next up will be an SP9/PH12 when I recover from this project. Now time to crack a cool one and enjoy some tunes!

     photo Theater.jpg

    Yes the HSU VTF-3 helps the low end....


     photo TurntableSetup.jpg

     photo ST70.jpg

     photo LittleBear-1.jpg

     photo PreAmp.jpg

     photo PhonoStage.jpg

    Oh yeah forgot, I had to build a bucking transformer. 117v to the ST-70 and 110v to pre-amp.
     photo BuckingTransformer.jpg

    audiobill

    Posts : 270
    Join date : 2014-03-13
    Location : Philadelphia

    Re: ST-70 alive again!

    Post by audiobill on Fri Jan 02, 2015 10:56 am

    Looks great - I'd try pulling out your monitors at least 2 feet from front and side walls, if you can - imaging and sound staging will benefit greatly!!!

    batman7349

    Posts : 14
    Join date : 2014-12-08

    Re: ST-70 alive again!

    Post by batman7349 on Fri Jan 02, 2015 8:25 pm

    Bill, I can only do that when the wife is not around......

    audiobill

    Posts : 270
    Join date : 2014-03-13
    Location : Philadelphia

    Re: ST-70 alive again!

    Post by audiobill on Fri Jan 02, 2015 8:27 pm

    Hmmmmmm

    What's her trade-in value? Smile

    batman7349

    Posts : 14
    Join date : 2014-12-08

    Re: ST-70 alive again!

    Post by batman7349 on Tue Jan 06, 2015 9:21 pm

    She's a classic 56 model. Might be surprised at how much I could get for her Laughing

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