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Noise problems!

PostPosted: 07 Feb 2010, 19:36
by Dj NB
Hey dudes! I have a serious project coming and i need to record few things at home, so I noticed that a electrical buzz noise is on the background of the sound. Few days ago I bought a ground loop isolator, but it seems that it makes more problems instead of fixing. I contacted the company where i bought my isolator but they were bummed I they didn't know what to tell me. So I would appreciate if you have a solution for my problem.
Info plus:
-The noise is off, when laptop (where MV is running) is on battery mode
- My mixer (Ecler Nuo 2.0) has a rec out (RCA) which is connected with another PC where all is recorded with Audacity


thx

Re: Noise problems!

PostPosted: 07 Feb 2010, 20:00
by Marxon
Hi DJ NB.

Ground loop hum couldt have many reasons and
many solutions to fix it.
My english is not good enough to tell you electrical details.
but here some tipps to avoid them:
-try to us the same "clean" power cicruit for all your sound devices
-dont connect them to other circuits (maybe via video cable from graphik card to tv)
-try to use balanced connection or use a di-box with ground lift
-only one device in your device chain should be grounded (only do this if you know what you are doingy!)

marxon

Re: Noise problems!

PostPosted: 07 Feb 2010, 22:05
by abitmessie
Hey NB

Grab a DI Box with a ground left on it
bacckground info
http://www.soundonsound.com/sos/jun02/articles/diboxes.asp

http://www.zzounds.com/item--WHREDB1
you will need 2 of these 1 for left and 1 for right output channels
unless you can find a stereo DI

there is also this but a little more pricey but alot of reviews have been very positive.
http://www.zzounds.com/item--WHRPCDI

Re: Noise problems!

PostPosted: 08 Feb 2010, 06:47
by sinjintek
first you need to isolate exactly were in the audio path you are hearing the buzz. is it heard through the mixer (headphones/monitors/etc), or only in your recordings?

i notice you mention no sound when your laptop is running on battery mode, so it could be electrical interference. you could try using a different power outlet, or moving your laptop further from your gear. ALWAYS try to keep audio and electric power wires separated as much as possible.

Re: Noise problems!

PostPosted: 09 Feb 2010, 02:42
by Dj NB
sinjintek wrote:first you need to isolate exactly were in the audio path you are hearing the buzz. is it heard through the mixer (headphones/monitors/etc), or only in your recordings?

i notice you mention no sound when your laptop is running on battery mode, so it could be electrical interference. you could try using a different power outlet, or moving your laptop further from your gear. ALWAYS try to keep audio and electric power wires separated as much as possible.

thx fro the info, my laptop is really close to my tts and the rest of the gear. And yup, the noise can be heard everywhere (headphones, monitors, rec....)

Re: Noise problems!

PostPosted: 09 Feb 2010, 02:51
by abitmessie
There is a good chance that it is your laptop power supply
i remembered last night that i had a simular issue when i had a lone laptop from a friend
turns out it was due to the laptop power supply having a ground pin and not correctly grounded

this was corrected with an after market power supply such as
http://www.belkin.com/au/IWCatProductPage.process?Product_Id=418487

Re: Noise problems!

PostPosted: 09 Feb 2010, 11:45
by Dj NB
Well it makes sence, coz i tried on battery mode and there was no sound... hm

Re: Noise problems!

PostPosted: 09 Feb 2010, 18:40
by polocorp
yep, just buy a small adaptor so your three pin power plug becomes a 2pin plug

Image

Re: Noise problems!

PostPosted: 09 Feb 2010, 18:51
by abitmessie
polocorp wrote:yep, just buy a small adaptor so your three pin power plug becomes a 2pin plug

Image


unfortunately they have banned the sale of these adapters in Australia
but will work also

some say even just hack your power supply and remove the ground pin but to me that just doesnt seem safe!!!

Re: Noise problems!

PostPosted: 09 Feb 2010, 20:12
by Blackbrook
abitmessie wrote:some say even just hack your power supply and remove the ground pin but to me that just doesnt seem safe!!!


Exactly! This may work, but it is anything but safe :-(

I read somewhere that there are notebook power adapters that can deal with this problem - don't now how. Those are certified too, so no worries about the safety. Sorry that I can not post a link NB but I guess that google or a shop for electronics close to you can help ;)

Greetings,

Steve