Humming on a amp for iPhone -iPad at full volum

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  • sam_sam_sam
    Badcaps Legend
    • Jul 2011
    • 6037
    • USA
    #1

    Humming on a amp for iPhone -iPad at full volum

    The the problem with with amp

    Is that when you have the volume all the way up it hums so you can hear it when going from one song to another
    Is the problem in the power supply or the amp itself

    It about 7 years old

    I just wanting to know where to start
    Attached Files
    Last edited by sam_sam_sam; 07-16-2016, 07:44 PM.
    Tags: None
    • japlytic
      Badcaps Legend
      • Oct 2005
      • 2086
      • Australia
      #2
      Re: Humming on a amp for iPhone -iPad at full volum

      The AC adaptor pictured here is of the switching type - does the "hum" sound like regular AC mains or does it have a buzz?
      First, try using the amplifier with a different AC adaptor (around 12-14V @ 4A) and note the results.
      My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

        Comment

        • rhomanski
          nowhere man
          • Dec 2009
          • 5157
          • U S of A
          #3
          Re: Humming on a amp for iPhone -iPad at full volum

          Hum usually means some capacitor isn't filtering AC as good as it used too. What that means for your equipment is hard for me to say since I don't have anything like that. I have old amps and I've had that but it was on the power supply board and the hum was in both channels. When things are separated you can get impressed noise from wiring between the pieces.

          Oh okay, we posted at the same time japlytic. You probably are much more familiar with his equipment.
          Last edited by rhomanski; 07-17-2016, 12:54 AM.
          sigpicThe Sky Is Falling

            Comment

            • japlytic
              Badcaps Legend
              • Oct 2005
              • 2086
              • Australia
              #4
              Re: Humming on a amp for iPhone -iPad at full volum

              If you place your ear close to the power supply brick, do you hear 60Hz hum or buzz and if so, is it significant?
              My first choice in quality Japanese electrolytics is Nippon Chemi-Con, which has been in business since 1931... the quality of electronics is dependent on the quality of the electrolytics.

                Comment

                • sam_sam_sam
                  Badcaps Legend
                  • Jul 2011
                  • 6037
                  • USA
                  #5
                  Re: Humming on a amp for iPhone -iPad at full volum

                  Thanks for all of your replys this give me a place to start looking to fixing this problem

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