Karaoke Forums

I hooked up my laptop to a powered mixer in my basement over the weekend.
There was static and noise coming out of the speakers. At 1st I thought it could be the mixer. When I unplugged the laptop the noise went away.

So then I assumed it was the laptop as I was using the HEADPHONE out jack.
( this is a brand new laptop). SO I plugged in some heaphones expecting to hear the static and NOTHING BUT PERFECT SOUND. I unplugged the heaphones and still PERFECT SOUND from the laptop.

Could it be the CABLE I use ??? - What else would give me static and noise ?

Sounds like there is a problem with the 1/8" plug/connector. Like a TRS jack, those 1/8" plugs have multiple connection points that have to nestle right at the correct area of the female jack, or else you end up with a electrical ground loop.

It could be a problem with the tip, the internal insulation, or the washer that separates the cord conductor (shaft?) from the connecting block (base?).



Anyway, that is definitely your problem. Think about when you have your system on and you connect a 1/4" TRS or Phono jack to a live system, and before it is all the way in, you get the ground loop hummmmm. It is the same thing. Your 1/8" plug has some issue where the electrical signal is merging with the audio chain, creating the ground loop hummmmm.

So you just need a new cable.

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C Mc
KJ, FL

This is what's called a ground loop problem, extremely common when using laptops connected to a power supply. Search the forums for ground loops and you will see this has been discussed many times..

common solutions:
Hum-X - http://www.ebtechaudio.com/humxdes.html
Xitel - http://www.xitel.com/USA/prod_gli.htm

others may chime in with better solutions.....

That isn't a ground problem, he didn't describe hum.
Sounds like a bad cord or connection from the jack out to the mixer.

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

Lonman - he did say that the noise went away when he unplugged his laptop, that is classic sign of ground loop. There is no noise when you run off batteries but plug the cord in and you get noise, that is not a cable issue, that is a power issue. Unless I'm misunderatanding what he means by "unplugged the laptop"

I say ground loop, the power supplies for notebooks keeps getting cheaper and cheaper.

Static and noise is not typically how people describe a ground loop hum. I'd be shocked if that is the issue (no pun intended). To the OP, if it's a low constant hum that you're hearing, it would likely be a ground loop. By static do you mean a constant white noise (like when you tune an anolog TV to a non-existent channel)? Or is it sporadic? Try wiggling the cable at all connections and throughout the cable run. Does it happen as a result of you doing that? If so it's likely the cable or maybe a problem with the jack itself.

Does it only happen when music is playing or does it happen all the time. If it's only when music is playing it could be that something in your signal path is clipping. Give us a few more details and we'll get to the bottom of it for you.

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DJ Tony
Let It Rip Karaoke

if the laptop is unplugged and the problem goes away, it almost has to be a problem with the house power supply, right? you don't need to pay 60 bucks for a humX by the way. there is a ground loop filter available on amazon for 12 bucks. I ordered one. I'll let everyone know if it works. 12 bucks way better than 60.

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[glow=red]Yo sucka, we need this hea CHOPTER, and we need it now![/glow]

There is no HUM

What I meant was - "disconnect" the laptop from the mixer ( still plugged in electrically)

I have another cable that I will try and see if the "noise" goes away.

Laptop on its own --no noise or static
Mixer on its own - no noise or static

Only thing left I guess is the cable

I think you have it nailed there...do you have a external usb interface you can try?

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Music speaks to the heart in ways words cannot express.

Also try unplugging any television input from the laptop. That would usually be a hum but can be static from a leaky receiver too.

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[color=#ffff55]Mickey J.[/color]
Alas for those who never sing, but die with all their music in them.
-- Oliver Wendell Holmes, Sr.

I would say ground loop. Computer manufacturers are going cheaper than ever on their adaptors.

You need to get a little converter that changes your 3 pin laptop plug into a 2 pin.

OR

Break off the ground pin on the plug and then plug it in (without ground) (THERE IS SOME RISK INVOLVED IN DOING THIS - BUT IT HAS WORKED LIKE A CHARM FOR ME FOR THE LAST 3 YEARS).

The risk of electric shock is relatively low from a plastic laptop

YAYYYYY all fixed. Has been working for me for the last 3 years.

Vic in Sydney

Ground loops have nothing to do with the quality of the power supply. Even the best equipment available is subject to ground loops when A/C power is not planned properly. I won't clutter this thread with it but I'm going to post a new thread describing ground loops so hopefully all here will benefit from what actually causes them.

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DJ Tony
Let It Rip Karaoke

Actually yes - I just purchased this last week but didn't get to use it and was even thinking about sending it back?..... Would this give me a better sound than the stock sound card and eliminate most noise or static??

http://pro-audio.musiciansfriend.com/pr ... B&ZYXSEM=0

This is the worst possible advice. Removing the electrical ground is simply dangerous. In an interconnected system you're not just worried about the device you removed from the electrical ground but every device it is connected to through a shared ground path. Your USB, Audio, VGA, S-Video, RCA and Coax connections all interconnect the grounds of your equipment. So if say you mixer short circuits, the voltage could come down the ground connection of the audio cable that is connected to your laptop and not only could it fry your laptop but could also cause you a nice shock.

Please for gods sake don't give electrical advice if you do not understand how electrical systems work. You're gonna get someone killed.

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DJ Tony
Let It Rip Karaoke

This is dangerous and stupid advice.

You should be getting your Darwin Award any time now.

Wish I had your luck. I've been zapped before from a poorly grounded outlet through no fault of my own. Gettin' kicked by Uncle Nat's mule hurt less.

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Dave's not here.

Did the other cable work? If not I would at least try the usb interface you purchased before deciding wether to keep it or not.

Funny how some don't read the thread before posting huh?

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Music speaks to the heart in ways words cannot express.

OMG- I didn't expect this to get so charged up...

I did this based on advice I received on this very forum a few years ago. No one disputed it at the time for some reason.

In any case, I have researched it and whether or not there is real cause for concern is disputable.

I can say however that I have been hum free ever since. Note that this is my second suggestion. Just in case and not to tinkle any one off- I have gone in and edited my post to say that "there might be some dangers associated with doing this".

I'd be interested to know if anyone has themselves been injured by doing this, or if you know anyone that knows anyone that has been.

Thanks

Vic in Sydney.

I got a bad enough shock that it actually burned my fingers where I grabbed a mic on a system that was improperly grounded - ie prong taken off. Not to mention it hurt like hell! If it was someone from this forum, then others that would have tried to tell you otherwise didn't see it. I have suggested a ground lift (3 prong to 2 prong adapter) for a quick test to see if that was the problem, however would never leave it as a permanent solution & would opt for something safe like the Ebtech products.
You have just been lucky.

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LIKE Lonman on Facebook - Lonman Productions Karaoke & my main site via my profile!

It depends on what your definition of hurt is. In my case all I know is I hit a power chord, and stepped up to the mike to sing. I woke up a few minutes later flat on my back, with half my mustache burned off and second degree burns on my face and lips. People that saw it said the flash-bang was "awesome."

The PA system was smoking almost as much as I was.

I've been downright OCD about making sure my equipment is safely grounded since.

There's no dispute about it. Improperly grounded PA systems can and will kill you if you give them the chance.

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Dave's not here.