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    Add balanced input to M-125?

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    ptstucky

    Posts : 1
    Join date : 2018-01-03

    Add balanced input to M-125? Empty Add balanced input to M-125?

    Post by ptstucky on Fri Feb 23, 2018 2:31 pm

    Hi all,

    Apologies up front if there is already a thread on this, but I did not find the answer after a cursory search of the board.

    Has anyone tried adding a balanced XLR input (in place of or in addition to the unbalanced RCA ins) on the M-125 monoblocks?  

    If space allows, I would be interested in adding some XLR jacks and a Jensen transformer, but would like to know if others have attempted this.  What are some potential problems one should consider before attempting?

    Thanks for any ideas.

    Best,
    Paul


    Last edited by ptstucky on Fri Feb 23, 2018 3:00 pm; edited 1 time in total
    deepee99
    deepee99

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

    Add balanced input to M-125? Empty Re: Add balanced input to M-125?

    Post by deepee99 on Fri Feb 23, 2018 2:55 pm

    ptstucky wrote:Hi all,

    Apologies up front if there is already a thread on this, but I did not find the answer after a cursory search of the board.

    Has anyone tried adding a balanced XLR input (in place of or in addition to the unbalanced RCA ins) on the M-125 monoblocks?  

    If space allows, I would be interested in adding some XLR jacks and a Jensen transformer, but would be interested to know if others have attempted this.  What are some potential problems should one consider before attempting?

    Thanks for any ideas.

    Best,
    Paul
    Hi, Paul, space would be a consideration, for one thing. I believe Bob L. did address this matter at some point. Might PM him.
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    B&WTube

    Posts : 31
    Join date : 2019-08-19

    Add balanced input to M-125? Empty Re: Add balanced input to M-125?

    Post by B&WTube on Fri Feb 14, 2020 12:40 am

    Anyone do the XLR’s on a M125?
    KenGaler
    KenGaler

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    Join date : 2019-10-11

    Add balanced input to M-125? Empty Re: Add balanced input to M-125?

    Post by KenGaler on Fri Feb 14, 2020 1:09 pm

    B&WTube wrote:Anyone do the XLR’s on a M125?

    That does seem like a reasonable thing to do. It galvanically isolates the input and eliminates ground loop issues. They may cause a slight sonic change.

    It's probably easier than lifting the audio gnd off the chassis.

    tubes4hifi
    tubes4hifi
    Admin

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    Join date : 2008-11-30

    Add balanced input to M-125? Empty Re: Add balanced input to M-125?

    Post by tubes4hifi on Thu Feb 20, 2020 3:37 pm

    two ways to do balanced inputs, one is simply use an XLR connector, and tie the GND and - legs together.
    The better way is to use an isolation transformer, a good one costs around $80 each (Lundahl or CineMag)

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