Laptop power supply noise.

[jasmeece]

Is there any way to clean up the noise generated when I run my laptop through my PA? I know that I can go on battery but I have been burnt by that battery draining away during the set up and then not being there for the performance. I just want it to be a bit quit I settle for a low hum.

[BertKoor]

Some possibilities:
1: use a line insulator / DI to get a balanced signal
2: disconnect ground of power supply (or do connect it, since that can be a problem also)

[Lagrange]

I've used this one in a live setup. What you do is allow the noise to play through the ap and get a finger print of the noise. Then you use it to filter out specific noises.

HTH

L

[Patchen]

use a ground lift. common problem with laptops and external hard drives. They either need to be on a different
circuit or the ground needs to be lifted. use one of those funky grey adaptors if your in the us

[jasmeece]

Thanks for the Ideas, I will try them

[pwedza]

I had the same type of problem.

see: http://www.kvraudio.com/forum/viewtopic ... light=[url][/url]

I bought an Ebtech line level shifter from zzounds. I believe your problem, like mine, is ground loop.
http://www.epanorama.net/documents/groundloop/

I was getting every little sound coming through my computer (even mouse noises). Look around for ground loop eliminators.

This is what fixed my problem (-10db to +4db line level shifter):
http://www.zzounds.com/item--EBTLLS2PKG

This is to eliminate hum (like the above, placed between speakers and sound output):

This goes between the computer and the wall: http://www.zzounds.com/item--EBTHUMX

Other choices:
http://www.whirlwindusa.com/dirbox.html#direct2

I was a bit frustrated for a while trying to figure out what the deal was but now I have a really clean sound and all is good.

Hope that helps and good luck.

[pwedza]

These should knock out your problem. That way you don't have to settle for even a low hum.

[pwedza]

oh, forgot to add this one:
http://www.zzounds.com/item--EBTHE2PKG