For quite some time I've been plagued by weird electrical problems. I have an old pair of Roland studio monitors - nice, chunky things, give a pleasant sound, but unfortunately a few unpleasant ones, too.
But only when my (visual) monitor is switched on!
It was fine with a different, but inferior monitor - no unpleasant noise to be heard. The annoying thing was that the quality of the noise changed with the image displayed on the monitor, sometimes exhibiting no noise at all. What's one to do, apart from defenestrate various electrical gadgets?
Anyway, I got a new pair of computer speakers which were fine, and thought nothing of it - if I want quality, I have a pair of Shure E3Cs, so no problem. Until I got a new monitor over the summer - plugged it into my laptop, and what do I see? Interference bars, damnit. But I noticed that it went away as soon as I disconnected my laptop from the mains.
A thought occurs.
No, it's not possible to run my laptop from batteries indefinitely. But, due to the process of elimination, something is dirtying the mains supply and ruining things for the rest of us. Laptop power supplies aren't the best in the world and are an obvious culprit, but is there something I can do about it? A few searches suggested that there was noise across the earth which both laptop, monitor and speaker are connected to, and does well to explain why things are just dandy when the laptop is disconnected.
There is an awful lot on the subject of ground loops, which is what I was subject to. I chose the easy way out and disconnected the earth pin from the kettle lead that plugs into the laptop power brick. This is not something anyone would really recommend due to the whole purpose of earth for safety (so if you do it and something bad happens, you didn't hear it here), but considering it's a sealed plastic power brick with a two-pin output, you aren't losing anything. The important thing is my problem is solved and everyone is happy. Just don't reuse that lead for your kettle, fer'chrissakes.
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