UMC 204HD/404HD: Do I need to block phantom power in a line in to record a skype call

  1. #1 by Antonio Vega on 07-11-2018
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    Posts: 2

    UMC 204HD/404HD: Do I need to block phantom power in a line in to record a skype call

    Hi. Hope this is the right place for this. Here's my problem, I really hope someone can help.
    I bought a UMC 404HD usb interface. I will be doing a podcast and interviewing people via Skype. I need phantom power on to power my mic in line 1. And I need to run a 1/8" to xlr cable from the headphone jack of my laptop to the line 2 of the UMC 404HD in order to record the audio from my guests. I THINK I don't need to block the phantom power right? The XLR to 1/8" cable would not take the phantom power to the laptop, right? I'd like to just turn off the phantom power in line 2 but the UMC interfaces only have one switch for all the line ins. I'm worried about damaging my laptop with phantom power from the UMC. Is it ok? Will phantom power not make it to the laptop? Are laptops usually ok even if phantom power is sent to the headphone jack? Or do I need to buy some kind of phantom power blocker? I saw a couple that sell for like 70 bucks. I'd rather not have ot spend the money since that seems crazy expensive for something I may not even need (ever).

  2. #2 by Robert Lofgren on 07-12-2018
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    Posts: 5,129
    I would NOT use the 1/8-xlr cable adapter because of the concerns that you mention.

    Phantom power will travel to the headphone port on your computer and while some computers will happily ignore phantom power on it, other computers will take a dive...

    But your interface has combo connectors so you can use an 1/8-ts cable (or one with two ts if you need stereo) and this input is not carrying phantom power so you will be safe.

    As an alternative, you can use the inserts on the back of your interface for the same purpose.

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  3. #3 by Antonio Vega on 07-12-2018
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    Wow.... can't believe that didn't occur to me. Seems so obvious now but I guess that's my lack of experience in these things coming through. Yeah, a 1/8" to 1/4" cable into line 2 should do the trick since I have no idea if my laptop would be ok with phantom power, nor do I want to find out by trial and error.