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    12AU7W / 6189 Hum

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    jimmeq

    Posts : 32
    Join date : 2017-02-24

    12AU7W / 6189 Hum

    Post by jimmeq on Thu Jul 19, 2018 3:26 pm

    In my Distortion & Hum post I mention the hum was (is) created by the Tung-Sol tubes.

    I exchanged the center driver tube one by one and each new production Tung-Sol 12AU7W / 6189 introduced a very noticeable hum even with the volume turned down. This is not a slight against Tung-Sol...

    They are on the compatible "list".

    Three bad tubes? Really?? affraid

    I can exchange them; I just find it very strange I'd get three bad new tubes.

    Anybody else experience anything like this even with other tube brands?

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    corndog71

    Posts : 673
    Join date : 2013-03-19
    Location : It can get windy here

    Re: 12AU7W / 6189 Hum

    Post by corndog71 on Thu Jul 19, 2018 3:32 pm

    jimmeq wrote:In my Distortion & Hum post I mention the hum was (is) created by the Tung-Sol tubes.

    I exchanged the center driver tube one by one and each new production Tung-Sol 12AU7W / 6189 introduced a very noticeable hum even with the volume turned down. This is not a slight against Tung-Sol...

    They are on the compatible "list".

    Three bad tubes?  Really?? affraid

    I can exchange them; I just find it very strange I'd get three bad new tubes.

    Anybody else experience anything like this even with other tube brands?


    Dare I ask, who did you buy them from?
    avatar
    peterh

    Posts : 1070
    Join date : 2012-12-25
    Location : gothenburg, sweden

    Re: 12AU7W / 6189 Hum

    Post by peterh on Thu Jul 19, 2018 3:50 pm

    jimmeq wrote:In my Distortion & Hum post I mention the hum was (is) created by the Tung-Sol tubes.

    I exchanged the center driver tube one by one and each new production Tung-Sol 12AU7W / 6189 introduced a very noticeable hum even with the volume turned down. This is not a slight against Tung-Sol...

    They are on the compatible "list".

    Three bad tubes?  Really?? :affraid:

    I can exchange them; I just find it very strange I'd get three bad new tubes.

    Anybody else experience anything like this even with other tube brands?

    I had some kind of similar experience with 5963 tubes. I junked them and installed
    JJ ECC82 instead, and the amp is dead quiet and have been about 1000h .

    It's not uncommon to have filament <> cathod leakage

    jimmeq

    Posts : 32
    Join date : 2017-02-24

    Re: 12AU7W / 6189 Hum

    Post by jimmeq on Fri Jul 20, 2018 1:37 pm

    corndog71 wrote:
    jimmeq wrote:In my Distortion & Hum post I mention the hum was (is) created by the Tung-Sol tubes.

    I exchanged the center driver tube one by one and each new production Tung-Sol 12AU7W / 6189 introduced a very noticeable hum even with the volume turned down. This is not a slight against Tung-Sol...

    They are on the compatible "list".

    Three bad tubes?  Really?? affraid

    I can exchange them; I just find it very strange I'd get three bad new tubes.

    Anybody else experience anything like this even with other tube brands?


    Dare I ask, who did you buy them from?


    Tube Depot.

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    Re: 12AU7W / 6189 Hum

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