Quantcast

Maximum PC

It is currently Fri Aug 22, 2014 9:55 pm

All times are UTC - 8 hours




Post new topic Reply to topic  [ 2 posts ] 
Author Message
 Post subject: Hearing Graphics
PostPosted: Thu Jan 02, 2014 12:01 pm 
8086
8086

Joined: Sun Jun 10, 2012 12:23 pm
Posts: 50
I currently have a cable running from the audio out of a Macbook Pro to the audio in of my PC. When it is connected to the Macbook I hear a lot of background noise on my PC audio out. Unplugging it from just the macbook pro gets rid of this noise. Oddly enough, leaving the cable in but "muting" the input on my PC doesn't stop the noise.

What I'm finding weird is that I hear an additional, distinct noise when certain graphical changes happen on my monitor. If the page scrolls in the browser, I hear it. If I put my mouse over a tab in FireFox, I hear it. If I open a new application, I hear it. Any graphical change gives a distinct "click" noise. I've rerouted the cable so that it is much further away from the monitor and attempted to put some "poor man's shielding" on it but all that did was lessen the "sound of graphics" (sounds like something a 60s LSD user would say lol). This happens with both my shiny new IPS DVI monitor and my old LCD monitor using VGA/DVI.

Can this be stopped by changing DVI cables?


Top
  Profile  
 
 Post subject: Re: Hearing Graphics
PostPosted: Thu Jan 02, 2014 1:24 pm 
Smithfield
Smithfield

Joined: Sun Jun 18, 2006 7:37 pm
Posts: 5229
If I'm understanding this setup, the Macbook is connected to the PC only from its line out to your PC's line in, with nothing else. I'm also assuming this is a desktop PC with a discrete graphics card. And if it isn't, it'll be helpful to know the exact setup :D

I would try replacing the audio cable first, preferably one with chokes on both ends. Or trying this with another device in the line in.

I can't put the blame on the DVI cable, you can read my explanation in the spoiler box.
Spoiler: show
DVI uses a continuous data stream in a format similar to VGA, i.e., some syncing and RGB values. Even if you move the mouse or whatever, the signal wouldn't change much. Plus DVI operates at 1.2 Vpp (A picture of a DVI signal), which is too low of a voltage to cause significant amounts of EMI.


Top
  Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 8 hours


Who is online

Users browsing this forum: No registered users and 11 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group