Hum USB issue

Discussion in 'Support & Bug Reporting' started by JayJay, Jul 5, 2018.

  1. JayJay

    JayJay New Member

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    Hi all,

    Only new to the forum but I have had my amplifire over 2 years now.

    i have an issue where I have a lot of (what I have identified as) 120Hz hum on the unit when playing normally. When I plug into the USB on my computer the hum goes away... The hum is there as well when not the lead is not plugged into the guitar, so it is not originating from the guitar.

    I have looked around online, and it seems to indicate that I have a ground loop issue, my question is, how the hell do I get rid of it? Most forums etc. seem to apply to stereo equipment, where the resolution is to remove a piece of hardware from your signal chain, but I obviously can't do that :) Also I have tried to squeeze it out on the sound gate, but I have to crack it so high that the sound trails off so unnaturally.

    My signal chain is: guitar -> lead -> amplifire -> lead -> tube cake power amp -> cable -> cab
     
  2. Jace Nuzback

    Jace Nuzback Senior Member

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    Jayjay,
    What are you using to power everything?
    Jace
     
  3. JayJay

    JayJay New Member

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    Hey Jace,

    So for the Atomic I'm using the supplied power supply, computer and power amp are likewise through independent power supplies all into wall sockets.

    I did a test last night as well and ran through an old tube amp in place of the atomic unit and power amp and had none of the hum issues.

    From thinking it out so it seems to me (with little or no knowledge of grounding theory) that the problem is the atomic itself is not grounded properly? Can that even happen? I'm really confused here.
     
  4. Jace Nuzback

    Jace Nuzback Senior Member

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