Electrical noise when laptop/pc on mains

[admin_exported]

Hello. When i use my Dell laptop or pc connected to my DAC (Cyrus Pre Xpd) via USB (Wireworld cable) and on the mains electricity i get a lot of static and generally awful sounding electrical noise. The problem does not happen when the laptop is run on battery.

I have tried different power and USB leads which made no difference. I have seen posts on other forums about cutting earth wires but dont feel this is the way forward or to be recommended.

Can any of you good people help please?

Thank you.

 

[Andrew Everard]

Do the computers have an optical digital output? If so, using this may solve the problem, as it will sever the direct electrical connection from PC to hi-fi.

 

[Anonymous]

No optical out, sorry.

The differance the Wireworld cable made was exceptional. I am now a convert.

 

[Andrew Everard]

Its power supply noise, I'm afraid. Using the computer on batteries may well be the only answer

 

[PJPro]

You want a USB to Optical adapter like this. Maplins used to do one....but not any more.

 

[Anonymous]

I have tried a Asus netbook on mains and theres no interference. So the problem lies with the Dell PSU.

Thank you.

 

[John Duncan]

My Sony Vaio does it too. Using a DACMagic on USB helped enormously, but didn't eradicate it completely. Get the sound off board by using PJPro's suggestion or by streaming to an Airport Express or similar.

 

[idc]

Try a ground loop isolator, going by reviews in Amazon they help to stop electrical noise coming from a PC.

 

[Anonymous]

Had the same problem with both a dell xps and a dell inspiron, so i took a chance and bought a ground loop isolator from Amazon, it was only £6.I connected it between my dac and amp and hey presto it worked . There was no interference whilst using the laptop with the psu. So problem solved .....well not totally because when i then switched to using the laptop on battery power the isolator introduced a higher pitched level of interference.If you removed the isolator and run the laptop on battery only everything was ok.

So in conclusion ,if you use your laptop with the psu all the time, then maybe an isolator will work for you.However if you switch between psu and battery then maybe an optical lead or airport express is the answer, unless you like changing cables everytime.

 

[PJPro]

Take a look at this. These seem to be highly regarded. Converts from USB to optical....like a mini soundcard. And it does not upsample.