Marantz 1150 D phono hum issue

Discussion in 'The Projects Forum' started by Meerkat 67, Aug 17, 2015.

  1. Meerkat 67

    Thread Starter New Member

    Jan 29, 2015
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    I recently acquired a Marantz 1150D integrated amp that has a hum on the phono inputs only..I have cleaned all controls and checked for poor grounds etc but nothing.. Anyone have the same problem and can steer me in the right direction.? \I do not know if this amp is rare but my son was going to recycle it just beforeI took it Cheers Wayne
     
  2. Dodgydave

    AAC Fanatic!

    Jun 22, 2012
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    Is the hum there with the phono inputs shorted to ground?
     
  3. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    Every time I have encountered audio 'hum' problems it has always been due to a grounding issue with the source audio(phonograph in your case) or the amp.
     
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  4. Meerkat 67

    Thread Starter New Member

    Jan 29, 2015
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    I have tried the phono shorting plugs and the hum is still there... The issue, at least from what I can see, is that the problem would be in the preamp board area.. I do not have a service manual, but will try to get one to proceed. As I said I am not familiar with this Marantz Model..At this point the only issue is the phono circuit, all other inputs are fine and hum free. Once I get a schematic/service manual, this will help..

    Thanks for the replies and if anyone else had a similar issue let me know...

    Cheers... Wayne
     
    Last edited: Aug 18, 2015
  5. Dodgydave

    AAC Fanatic!

    Jun 22, 2012
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    Last edited: Aug 18, 2015
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