IPhono2 hum

Discussion in 'Audio Hardware' started by Urobouros, Jun 8, 2018.

  1. Urobouros

    Urobouros Member

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    While it sounds good at low to moderate volumes, it’s definitely noticeable at higher volumes and very present with headphones. I tried every grounding possibility, changed cables, moved the power cables away, changed the load and gain settings but nothing clears up the hum. I’ve seen some threads on other sites about QC issues but I like the way it sounds other than the hum. My other pre didn’t have any problems with noise so I don’t think it’s my space. I don’t want to return it if I don’t have to since it was rather discounted and I doubt they’ll go for an exchange for a new one :). Any ideas?
     
  2. Corycm

    Corycm Well-Known Member

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    For funsies, have you tried some different outlets/unplugged everything on that circuit?
     
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  3. mcherry

    mcherry Spam Slayer ☠️ & Moderator Extraordinaire

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    I think @Jango went through various scenarios on this.
     
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  4. displayname

    displayname Well-Known Member

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    The only thing that eliminated my hum was adding a ground to my outlet and having that outlet dedicated to audio only. It could be your iPhono2 causing the hum, or it could be that any more sensitive equipment is going to pick up a hum that wasn't previously present. It can be tricky to trouble shoot. Maybe if you live near a HiFi store or someone was a already dedicated powerline you could ask if you could pop in the iPhono to their system and see if it's still present. That option might not be realistic tough.
     
  5. Urobouros

    Urobouros Member

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    Yep. I switched outlets and also tried isolating it on its own circuit. It definitely has more gain than my previous pre. While trying different settings this morning I found a higher gain on the pre gets a pretty good speaker output without hearing the hum except between songs. Same with the headphones. I’m honestly a little torn as a like the tone but don’t know if the hum won’t drive me nuts in the long run...
     
  6. Jango

    Jango Well-Known Member

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    Do either your receiver or turntable use 3-prong power cords? I’m guessing not.
     
  7. Jango

    Jango Well-Known Member

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    It will drive you nuts and you shouldn’t need to live with it. You can find more detail on my journey to a solution here:
    http://forum.vinylmeplease.com/index.php?threads/heres-your-forever-phono-stage.4313/page-11

    It could ultimately be the wallwart, but I never got around to testing it with another one because I didn’t have a 15v available. My long term fix was to buy this: https://www.musicdirect.com/accessories/iFi-Groundhog-Ground-Control
     
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  8. Urobouros

    Urobouros Member

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    Neither the TT nor the pre have 3 prongs. The groundhog is pretty cheap so will prolly give it a whirl. Of course, I could always return it towards... :)
     
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  9. Jango

    Jango Well-Known Member

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    I think it’s your best bet. One thing to note is that you’ll need an IEC power cord to connect it to.
     
  10. Urobouros

    Urobouros Member

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    I have a bunch of those that were surplus at work ;)
     
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  11. Urobouros

    Urobouros Member

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    The Groundhog came today and the hum is gone baby! Thanks @Jango!!
     
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  12. Jango

    Jango Well-Known Member

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    Excellent! I’m glad that did the job.
     
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