You are here

SoundCard interference noise

For anything relating to music-making on Windows computers, with lots of FAQs. Moderated by Martin Walker.

Re: SoundCard interference noise

Postby Martin Walker » Thu Sep 01, 2005 3:49 pm

It's not cleaning up the PSU, but breaking the ground loop that gets rid of these background noises.


Martin
User avatar
Martin Walker
Moderator
Posts: 15126
Joined: Wed Jan 13, 2010 9:44 am
Location: Cornwall, UK

Re: SoundCard interference noise

Postby Martin Walker » Thu Sep 01, 2005 3:56 pm

James - if your powered monitors have balanced inputs then a balanced cable will do the trick for you.


Martin
User avatar
Martin Walker
Moderator
Posts: 15126
Joined: Wed Jan 13, 2010 9:44 am
Location: Cornwall, UK

Re: SoundCard interference noise

Postby James Covell » Thu Sep 01, 2005 8:03 pm

Hi everyone,

Well... I tried the balanced cables - unfortunately they didn't solve the problem. In fact they were worse for picking up general noise. So as a last resort I disconnected the earth from the laptop power supply. Perfect - no interference or noise what so ever. As for safety issues (see ground loops thread)... I'm not convinced that it's such a major problem. I know someone with a Samsung laptop (only a year old) and it's power supply isn't earthed at all. Take radio/cassette players, they have a standard two pin 'figure of eight' connection - that's mains power straight into the unit.

Luis and everyone else with this problem - just get rid of the earth on your power supply. Then you can get on with the important stuff like making music!

James
-Big thanks to everyone for their input.
James Covell
New here
Posts: 6
Joined: Sun Sep 21, 2003 12:00 am

Re: SoundCard interference noise

Postby jammer » Fri Sep 02, 2005 12:16 am

James Covell wrote:Luis and everyone else with this problem - just get rid of the earth on your power supply. Then you can get on with the important stuff like making music!

James
-Big thanks to everyone for their input.

just remember ... your risking killing yourself or others.
User avatar
jammer
New here
Posts: 4
Joined: Wed Jan 12, 2005 1:00 am
Location: Frome, UK

Re: SoundCard interference noise

Postby Martin Walker » Fri Sep 02, 2005 3:12 pm

The big difference between those laptops with a figure of eight mains cable and the ones that are earthed tends to be metalwork on the case i.e. plastic cases generally have 2-wire mains cables, largely metal ones have 3-wire mains cables. if you remove the earth this will be floating, and in a fault condition could become live and be extremely dangerous.

On your own head (or heart) be it :shock:


Martin
User avatar
Martin Walker
Moderator
Posts: 15126
Joined: Wed Jan 13, 2010 9:44 am
Location: Cornwall, UK

Re: SoundCard interference noise

Postby James Covell » Sat Sep 03, 2005 4:56 pm

Hi Martin,

My laptop case is entirely plastic, and the power supply is a generic unit manufactured by a third party company. On the other hand my portable hard drive has a solid metal case. The power supply for this uses a 2 pin figure of 8 plug! - this MUST be breaching safety regulations.

James.
James Covell
New here
Posts: 6
Joined: Sun Sep 21, 2003 12:00 am

Re: SoundCard interference noise

Postby James Covell » Sat Sep 03, 2005 5:01 pm

just remember ... your risking killing yourself or others.

I was wrong to advise anyone else to do what I've done and I take that back. Do what you know is safe.
James Covell
New here
Posts: 6
Joined: Sun Sep 21, 2003 12:00 am

Re: SoundCard interference noise

Postby Martin Walker » Mon Sep 05, 2005 12:18 pm

James Covell wrote:Hi Martin,

My laptop case is entirely plastic, and the power supply is a generic unit manufactured by a third party company. On the other hand my portable hard drive has a solid metal case. The power supply for this uses a 2 pin figure of 8 plug! - this MUST be breaching safety regulations.

James.

Not if it's double insulated - many hi-fi amps, CD players, and so on have both metal cases and 2-wire mains leads with no issues.


Martin
User avatar
Martin Walker
Moderator
Posts: 15126
Joined: Wed Jan 13, 2010 9:44 am
Location: Cornwall, UK

Previous