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    Mechanical hum: power transformer

    2turbos
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    2turbos


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    Join date : 2009-09-20
    • Post n°1

    mechanical hum - Mechanical hum: power transformer Empty Mechanical hum: power transformer

    Post by 2turbos Wed Oct 18, 2017 4:55 pm

    I have a hum problem with my Stereo 70. It's mechanical, no detectable  hum in the signal on the outputs.

    I assume it has to do with the way the transformer mounts to the chassis. If I put a heavy weight on it then the buzz stops.

    Any way to isolate the transformer mechanically?


    Last edited by 2turbos on Wed Oct 18, 2017 4:56 pm; edited 1 time in total (Reason for editing : grammar)
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    Bob Latino
    Bob Latino
    Bob Latino
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    • Post n°2

    mechanical hum - Mechanical hum: power transformer Empty Re: Mechanical hum: power transformer

    Post by Bob Latino Wed Oct 18, 2017 7:51 pm

    2turbos wrote:I have a hum problem with my Stereo 70. It's mechanical, no detectable  hum in the signal on the outputs.

    I assume it has to do with the way the transformer mounts to the chassis. If I put a heavy weight on it then the buzz stops.

    Any way to isolate the transformer mechanically?

    Get FOUR 00 (double zero) flat neoprene plumbing washers and place them between the transformer and the top of the chassis. These will absorb most of the mechanical vibrations of the power transformer. Don't overtighten on top of these washers or you will flatten them out and they will loose their ability to absorb the vibrations.

    All VTA amps have "isolation washers" between the power transformers and the chassis.

    Bob
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    2turbos
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    2turbos


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    • Post n°3

    mechanical hum - Mechanical hum: power transformer Empty Re: Mechanical hum: power transformer

    Post by 2turbos Wed Oct 18, 2017 8:07 pm

    Bob Latino wrote:
    2turbos wrote:I have a hum problem with my Stereo 70. It's mechanical, no detectable  hum in the signal on the outputs.

    I assume it has to do with the way the transformer mounts to the chassis. If I put a heavy weight on it then the buzz stops.

    Any way to isolate the transformer mechanically?

    Get FOUR 00 (double zero) flat neoprene plumbing washers and place them between the transformer and the top of the chassis. These will absorb most of the mechanical vibrations of the power transformer. Don't overtighten on top of these washers or you will flatten them out and they will loose their ability to absorb the vibrations.

    All VTA amps have "isolation washers" between the power transformers and the chassis.

    Bob

    Thanks Bob. I was thinking along those same lines but wanted to check with forum members to see what they had done.
    Sounds like this problem already has a solution.
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    mechanical hum - Mechanical hum: power transformer Empty Re: Mechanical hum: power transformer

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