Info on Ground Loops and Hum

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Not sure if this has all been covered but When I started to Dj'ing with a laptop, I soon found out that everytime I plugged the PSU into the laptop there was this 60hz hum and weired noise like hash noise from the changing curcuit of the laptop/PSU, Going back to my electronics college days me and a buch of guys use to be on C.B Radios and I recall having this huge desk mic, but every time I was to hit the ptt bar this thing would put out a 60hz hum over the audio ckt. no matter what I did, so I went to the library to look up audio curcuits, I recall one where they had to use a Audio isolaction transfomer and that cured the humm issues with my Audio on the big mic.
I wnent to radio shack and bought 2 Audio isolaction transfomers (one for each channel L & R) I applided this idea to my laptop audio output, and Wha-lar the 60 hz and hash noise stopped and now could turn up the audio pre gain with no noise or hum.

if your good with a soldering iron and like to make and or repair your own equipment check out the links:

http://www.cliftonlaboratories.com/userimages/softro29.jpg
http://www.lib.uchicago.edu/~dean/blog/isolation-transformer.png

if you would like to contact me about audio issues pleas P.M me
Tnx

Dj~Ez
 
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The most useful thing to know about ground loops is that the term is PLURAL. If you approach the problem with the mindset of a single loop - then you may be running in cirlces for a very long time. To solve the problem requires a systems mindset and a modular view.

Ground loops can also occur internally - down to a single faulty piece of gear.
 
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Had a hum/noise/static last night.
Newer looking venue but not great electrical (one of two outlest at gazebo was dead).

I plug everything into one power strip and that into one outlet. Rarely, very rarely, have an issue. Last night the second speaker was in a separate outlet and fed via wireless signal (alto stealth).

BOTH speakers had terrible noise/static/hum. Made no sense to me, put a 2 prong adapter on the power strip into the wall and it went away in both speakers.

Same equipment I use all the time without issues.
 
Had a hum/noise/static last night.
Newer looking venue but not great electrical (one of two outlest at gazebo was dead).

I plug everything into one power strip and that into one outlet. Rarely, very rarely, have an issue. Last night the second speaker was in a separate outlet and fed via wireless signal (alto stealth).

BOTH speakers had terrible noise/static/hum. Made no sense to me, put a 2 prong adapter on the power strip into the wall and it went away in both speakers.

Same equipment I use all the time without issues.
Be very careful using a "cheater" adapter to bypass ground .. it will void almost any liability insurance if something happens.
 
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Only if they catch you using it.

This is one of those .. "Just Say No" things. There are better solutions with power conditioners or hum-x units. Units that pull a lot of current (powered speakers/subs and amps) really need to have a power path to ground. One thing I would never risk.