Author Topic: Eliminating HUM on sound output  (Read 3313 times)

Eliminating HUM on sound output
« on: January 31, 2010, 09:21:40 AM »
Hi guys, hope everyone is doing well.

I originally setup my Trigger IO to connect to my desktop because the old laptop I had was not handling ASIO, even with ASIO4all it would not work. That was working just fine but it was inconvenient to move between the kit and the computer to make little changes and whatnot. I really wanted to run it all from a laptop so that I could change things without having to get up, also for portability.

 Well I got a second hand Dell Latitude D-820 and an external Hard drive for my sound library and it handles all of the software (SSD & ETrigger) just fine but I still had to output the sound. I ran a 3.5mm stereo cable from the speaker port on the laptop to the line in jack on my desktop and it carried the sound but there was an awfull HUM in the background. I really need to eventually get something better for my speakers but I'm using my logictech 5 speaker pc set at the moment.

 Anyway I did a little research about the HUM and found out that there is a device which eliminates it. It's called a ground loop isolator, maybe you guys already know about them but for those who don't I thought it worth a mention. It is basically a little in-line filter and let me tell you it works awesome. I have absolutely no noise on the line now at all. I imagine this would work if you have a HUM  when you connect to other devices as well like a real AMP or into a mixer, whatever your using if you get the nasty background HUM this should fix you right up.

Here is a link to this device. I bought it locally from Radio Shack. Just be sure that you get all of the adapters you might need depending on your setup, I had to purchase an extra RCA to 3.5mm converter so that I could use headphone plugs on both ends. I might try clipping all of the converters out and just soldering what i need in-line but even with them it works great. ----------------BZ

LINK:
http://www.radioshack.com/product/index.jsp?productId=2062214

Re: Eliminating HUM on sound output
« Reply #1 on: January 31, 2010, 01:34:22 PM »
I had the same problem with a Dell laptop in one of my rigs.  To break the ground loop, just snip off the third prong from the DC adapter.  This won't cause any problems as the only thing that is grounded by that plug is the adapter itself, which is sealed in plastic.

Problem should then go away completely.