Hi Guys,

Whats the problem here?

I have a 3 channel mixer. I use 2 CDJ200's on 2 of the channels, so i tried hooking up my laptop as the 3rd channel. My laptop has Traktor on it, so I thought I could use mp3's as effects and loops etc. Fine until i plugged it in. My laptop does not have a multi channel soundcard, so I just plugged it into the headphone out on my laptop. This works fine off the battery, bus as soon as i plug the laptop into the mains, i start getting a very loud feedback kind of sound. This is a problem because the battery life on my laptop isn't that great so eventually I have to plug it in. Any tips or troubleshooting (other then purchasing a multi-channel soundcard).

Cheers, DJ HARN.

The problem that you are experiencing is called a ground loop. This is a problem that is found in some PC motherboards or the AC power adapter.

Google "ground loop isolator". They're cheap and do the trick for me!

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Harn, Maplin do isolators called "Shark". Really good and only cost a tenner each.

Thanks for the advice folks. So If I buy one of these devices, where exactly will I plug it? Will it attach to the RCA cable that's going to my laptop?

DJ HARN.

Yup!

But really you want to look in to getting a proper audio interface - they really don't much for an entry level one.

Low tech solution - ducktape through the middle of your power plug - it isolates it from the grounding part of the power network, but you have to be careful with old installations and such, it worked just fine with mine... No humming etc...
But it's an alternative, use it with discretion

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quote:

Originally posted by Tarpex Low tech solution - ducktape through the middle of your power plug - it isolates it from the grounding part of the power network, but you have to be careful with old installations and such, it worked just fine with mine... No humming etc... But it's an alternative, use it with discretion

that's the worst solution ever! you might end up killing yourself!

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I'm still alive... And even though i touch the components!

Anyway, laughs aside, if any1 could elaborate on the death road i'm taking, i'd be glad, as i don't know much about electricity =)

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OK here's some tips about electricity:

1, Major (especially high voltage) work is best done naked, when you have just got out of the shower and have not towelled off yet. Barefoot is preferable.

2, You should only ever open your computer and attempt repairs after having rubbed a balloon on your head for a minimum of five minutes. Wearing a shell suit and velvet jacket is best advised (and looks good).

3, Negative electricity doesn't exist (duh - how can it?), it's all a conspiracy so don't worry about the blue or black wire. ever.

4, If you want to test for a ground loop in your kit, get a bit of wire and go from the ground to the live terminal. This usually solves most problems associated with earth hum or short circuits. It will also stop most items in your house from humming. Can't explain why but all the noise is gone forever when you do this. Great!

5, Just like you do with batteries, if you want to know if there is power from a wire or terminal, just lick it - if you get a slight "tingle" then you know it's live.

Hope that helps.

*legal disclaimer - TO ALL PEOPLE READING THIS: I AM JOKING - DO NOT DO ANY OF THESE - I DON'T WANT YOUR MUM SUING ME COS YOU HAVE ARE A DUMBASS.

I had an annoying buzzing when I connected up my DJ mixer to my stereo in the other room. Radio shack sells ground loop isolators, cheap:

http://www.radioshack.com/product/i...rentPage=search

It worked perfectly for me!