I Guess Its Called A Ground Loop Problem

davethangjam

davethangjam

New member
guys i recently got myself a sony vaio e series vpcea32en for music production cause i wanted to more mobile rig. I've been using desktop for recording for more than a year i have no issue with my desktop. when i plug my interface in my laptop with battery charging there's a lot of noise coming out from my interface (headphone and monitors output). I've read in the internet that its a grounding issues but most people who face grounding issues usually use 3 prong in their power supply but my power supply is only 2 prong so please help me. i know that a di box/ground loop isolator can fix the problem but i'm kinda bankrupt atm so please suggest some cheap ways to eliminate the noise. Thanks
 
Two things that you can try. First, try plugging the laptop into a GFCI (ground fault isolator) and see if the noise persists. If so, get out your soldering gun and find a place on the chassis (metal) of the laptop to connect a wire. Then connect the other end to a ground plug adapter (those silly two to three prong $.79 things) on the little green flag that sticks out where the round pin should go through. Both of these are cheap (almost free) if they work.

Also, if you are mobile and using a power source from a running engine (generator or vehicle) the ground loop is usually from the alternator/magneto. Try using a large car battery with a GOOD dc to ac converter. Then you can just recharge the battery later when you're done and be ready for the next time. Not as portable that way, but a lot longer battery life than your VAIO.
 
Sorry, first suggestion was an in home fix if you were getting the noise all the time. Never mind that bit.

Are you saying you're getting ground loop between the interface and the laptop when unplugged? That's a different animal altogether.
 
I'm thinking it's more likely just a poorly filtered power supply. What interface are you using? Is it USB powered, or does it have its own supply?
 
Yep - I'd go with the power supply too - not so common on Sony, but Dell is well known for it. The psu for your interface is probably not grounded - few seem to be nowadays, so with the computer not grounded either - any noise isn't a ground loop, because there is NO ground.

One really worthwhile thing to try is a ferrite loop - you see small ones in power cables for many products nowadays - but one really simple trick is to find an old blown speaker, and strip the magnet out of it - they're usually a torrid, so you wind the power cable that goes to the computer through it - perhaps ten turns. Secure with tape and try it. These can often solve the problem or at least reduce it. Worth a try if the obvious things don't solve the problem. if you try an extra ground wire - try the monitor output socket - the screw hole is normally attached to the chassis - and just touch the end on a metal water pipe and see if the noise changes.

In the UK, it's frowned upon to add a ground to a device that is what we call a Class 2 device - that is one that is isolated from ground with a 2 conductor power cable. Adding the ground can on our 230V mains actually mean the gizmo will fail our electrical safety test!
 
Or just run on battery when the noise really bothers you. Maybe invest in a second battery just in case. That's probably quickest and easiest. IDK how bad the noise is, but I'd be willing to bet it would be only a minor annoyance for tasks like editing and even some of the basic mixing. Remember that the noise only affects the analog connections. So run on battery during tracking. Then the recorded files don't have the noise, and won't ever pick it up, even if you hear it mixed in with the digital signal in monitoring. Run on batteries for the critical points of the mixing and the mastering stage.
 
i'm planning to meet up a laptop technician/electrician in a couple of weeks. i'll be testing new power supply if it works then i'll invest on it or maybe let the electrician modify the power supply. what do you guys thinks?
 
Have you tried running the laptop on power without the battery in it? My old laptop I used for mobile recording gave me clicks and pops when charging.

Worth a try? :thumbs up:
 
My fix was run it WITHOUT the battery in the laptop. Just run on the mains power.

This will probably be a total different thing but it's worth a try?
 
Did you try popping the case and connecting a wire between the monitor ground at the chassis and a two prong to ground adapter at the green tab?
I see you're in India. Do they have that type of adapter there?
 
If the computer power supply is a simple fixed voltage unit with nothing clever, then try a different power supply - this won't work with a few makes like Dell, who manage to code their power supplies so the computer recognises if a different PSU is driving it, and applies different levels of nuisance treatment. If it just says 15V DC or something - then a proper DC power supply can be sourced and try it.

The dropbox link does't work, by the way so I can't hear the noise.
 
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