Computer Interference When Using Instrument Cables

Discussion in 'Digital & Modeling Gear' started by DRS, Apr 25, 2013.

  1. DRS

    DRS Member

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    I usually go HD500>xlr cable>powered FRFR monitor for my sound and it's very quiet. But at home I decided to go HD500>1/4" instrument cable>front end tube amp for a change. I was greeted with the worst interference I've heard. Sounded like the command bridge of a UFO flagship. I quickly figured out that it was my laptop a few feet away. Turned off the laptop. No more interference. Is there much you can do except move the computer away from the HD? Is this a problem when using 1/4 cable to other power amps?
     
  2. DRS

    DRS Member

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    bump
     
  3. cliffc8488

    cliffc8488 Member

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    Unfortunately computers create nasty interference that gets into your pickups.
     
  4. Pietro

    Pietro 2-Voice Guitar Junkie Silver Supporting Member

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    Try this.

    I had some interference from a Mac laptop one time. I simply used the laptop on battery power while I needed to play. noise was gone.

    You can also sometimes just move the computer a little or rotate it and it'll make a difference.
     
  5. awdwon

    awdwon Supporting Member

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    I had an issue with terrible noise interference from my iMac with some of my gear and the solution was better quality shielded cables and using balanced cables when possible. You don't need to spend an arm and a leg, I've had great results with cables from Monoprice, some of the best and cheapest cables I've used.
     
  6. DRS

    DRS Member

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    OK
    So when I play my guitar sitting 3 feet from my laptop through either a conventional guitar>1/4 cable>tube amp/speaker cab or guitar>HD500>xlr cable>powered FRFR, there is no interference. And this is with a S-S-S strat. Yet if I go strat>HD500>1/4 instrument cable>tube amp>cab - awful interference. Same cable. Why wouldn't the computer come across the single coils regardless of other factors?
     
  7. FrankyNoTone

    FrankyNoTone Member

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    There seems to be something about the 1/4" outs from the HD's. I had this same UFO noise, although not so loud, in one of my configurations with the HD400.

    UFO: HD400--1/4"--mixer--1/4"--FRFR

    No UFO: HD400--XLR--mixer--1/4"--FRFR

    But I had no UFO in in various other combinations through the 1/4" HD400 outs so I suspect grounding (on the HD400) comes into play. Try putting the HD400 and the laptop on different power circuits to narrow down the root cause.
     
  8. trazan

    trazan Member

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    Is the noise there regardless of whether the guitar is connected though?
     
  9. camstudio

    camstudio Member

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    Shielding your guitar electrics may help reduce the interference.
     
  10. all6string

    all6string Active Member

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    sounds like electrical noise on circuit to me, move computer to different circuit or use power conditioner or battery backup type device and should do the trick y'all!!
     
  11. DRS

    DRS Member

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    My strat is shielded. It only makes the noise when I run 1/4 cable from HD500 to tube amp. No other occasion no matter how close I am to computer.

    I'll try running the HD500 off of a plug on another circuit.
     
  12. DRS

    DRS Member

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    So I experimented today and found out it only does it when the USB cable is connected from the HD500 to the laptop. Unplug the USB and bingo silence. How weird is that?
    So one combination of connections: HD500>1/4 cable to tube amp with USB connected. If any of these change, no noise. The guitar doesn't even need to be plugged in.
     
  13. Pietro

    Pietro 2-Voice Guitar Junkie Silver Supporting Member

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    What laptop?

    With my Mac... if I use the 2-prong power plug that comes with it, I get some buzz and hum. If I use the 3-prong power cord... no hum, no buzz...
     
  14. jb4674

    jb4674 Member

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    Try these:

    Turn off the wireless adapter
    Run it on battery power.

    What kind of laptop is it?
     
  15. Mullenski

    Mullenski Member

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    Probably your cables. I switched from XLR cables to speaker cables to go 11Rack --> Mixer --> K10s. Went from UFO to quiet. Everything sits right next to my Mac.
     
  16. DRS

    DRS Member

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    It's an Acer.
    As far as cables go, I don't have a lot of choice going into the front end of a tube head.
    Thanks for the info.
     

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