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    VTAST70, grounding, phono stage question



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    Join date : 2017-05-20

    VTAST70, grounding, phono stage question

    Post by rymi on Tue Jun 06, 2017 8:52 pm

    I have a VTA ST70 which I use with a simple passive preamp.

    My brother is giving me a Bugle 2 phono stage. Im concerned I might have a grounding issue using this with my tube amp. The bugle2 uses a switching power supply.

    Jim Hagerman states " the bugle2 must get an earth ground from the linestage or receiver via the connecting cables; otherwise there will be hum. If the inputs to the linsteage are floating, then add an extra ground wire to the Bugle 2."

    So the tube amp doesn't have an "earth" ground, so likely I am going to have a hum issue correct?
    And if so, what should I do about adding another path to ground for the phono stage?

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    Join date : 2008-11-30

    Re: VTAST70, grounding, phono stage question

    Post by tubes4hifi on Thu Jun 15, 2017 7:28 pm

    Doesn't your Bugle2 has a ground lug on it? But I guess it's not connected to earth ground. You'll need to run a wire from there to earth ground.
    Get a spare 3 wire computer cord, cut off the neutral and hot wires, leaving only the 3rd wire ground.
    Connect that to your Bugle2 ground lug, and then plug in the cord to an AC socket (make SURE you are only using the GROUND wire !!!!!!!!!!!)

      Current date/time is Thu Jul 19, 2018 11:32 am