Laptop static

[chiphead]

I've got two older Dell Latitude laptops that I was going to use as an audio source for drum less tracks. When I connect them via a mini stereo cable to either my TD3 module or to my Simmons amp, I hear a lot of static and electronic noise. The noise is variable with some clicks and pops. If I unplug the Dell power supply from either laptop and just run them on battery, the noise goes away and everything is completely clear. I have two different Dell power supplies and they both exhibit the same symptoms. Any ideas?
Thanks
Steve

[jameswadewilson]

I have exactly the same problem with a Toshiba laptop. I wonder if laptops without a ground on the power supply have the same problem.

This appears to be bus noise from the PC, it changes depending on what the PC is doing.

I don't have a fix for it except to maybe get an audio card and/or some kind of isolation box.

I just use an MP3 player instead.

[stickinthemud]

The problem with most laptops is that everything is crammed in together so tightly that it is difficult if not impossible to shield the components from electronic interference. This is why a lot of people use a USB or Firewire external sound card when using their laptops as a Digital Audio Workstation (as James alluded to).

I am a big proponent of the stand-alone DAW. Avoids all kinds of device and software conflicts. Granted, they don't have that slick GUI, but they do one thing and do it well, and most come with a host of very good effects.

[chiphead]

Thanks for the responses. Turns out I can get a solid hour+ by just running it on the battery so that's plenty enough time for me.

[daveybabes]

Me too

I had that too a few years ago with a Dell Latitude (amilo D) when i unplugged and ran on battery it stopped, it's interference coming through the earth, i had everything plugged into one double socket with 5 way extension, it seemed to cure it when i gave the PC it's own socket from on the other side of the room.

[ige87]

Yeah, thats a ground loop problem. The best way to cure it is to eliminate the loop either by moving plugs around or to get a power cleaner. Daveybabes, moving to another socket probably worked because they were both using separate mains feeds.

[John_J]

Oh, man! I have the EXACT same problem with my new Dell Inspiron 1420.
Any fixes?

[ige87]

Power cleaner? Or try connecting to different mains outlets.

[TriggerThis]

You need a DI box.

[ige87]

As long as it has a ground lift to eliminate the ground loop problem.

[cambrosi]

Can you give examples of a, D1? or a power cleaner? I'd really like to be able to run my laptop on power rather than battery.

[daveybabes]

mmm aha mmm

Here's some info on DI boxes, you can go from PC to DI and then to mixer then speakers or whatever ...

http://www.musiciansfriend.com/document?doc_id=102219

from what they say the whirlwind imp 2 looks cool at $39.99

Good luck

[ige87]

Have a look here. It explains what you need and why you need it. You should be able to go to any good music shop and ask for a DI box with ground lift and have them understand you. There are hundreds to pick from. This may be a good choice as it requires no power.

[chiphead]

Good stuff. Thanks everyone.
In reference to the ART ZDirect Passive DI that ige87 mentioned, this would need a 1/8 stereo to 1/4 stereo cable to run from the laptop to the DI input than a 1/4 stereo to a 1/8 stereo cable to run from the DI output to the input on my TD3, correct?

[ige87]

According to the website the output is XLR, so you'd need an XLR to 1/8. However, I've just realised that the DI box is only mono not stereo so it'll be no good if you want stereo sound to play along with. There must be a passive stereo one, anyone any suggestions?