Acceptable noise from analogue mixer?

I’m used to mixing ITB but recently bought a little Behringer mixer as I needed the headphone socket and my soundcard didn’t have one.

Anyway, when I turn the volume up on the mixer there is quite an audible ‘buzzing’ sound.  It’s not noticeable when the volume is only 50% up and music is playing.  I’m not sure if this is ‘acceptable ground noise’ or something else.

Also, when I open some programs on my PC the noise sort of changes in tone. 

When sitting at rest (no music playing) Abletons Spectrum shows noise across the spectrum (very low in volume, up to about -100db on the graph).

Any ideas?

I have the behringer xenyx 1204fx and it has the same buzzing sound. No idea what it is but its been driving me mad for months.

Computer based gear equals loads of radio frequency interference from them are you using shielded cables?

I have the Behringer Xenyx 1002 for the same reason - I also bought Belkin Pure AV Silver Series Digital Coaxial Audio Cable for about £14 expensive but cuts out alot off the noise - though if I ram the volume up over 75% then I do get noise



I suppose the ideal solution is to get a sheilded computer case if the exist

[quote]egg2 (25/08/2010)[hr]Computer based gear equals loads of radio frequency interference from them are you using shielded cables?[/quote]



No, but that will be my first payday purchase :wink:



Cheers.

good idea.

Make sure there are no power leads crossing audio leads, also check it not one of your connectors causing interference. It might borne any of these things but it’s worth a go

Cheers guys, I’m pretty sure its a standard ‘ground hum’ or whatever.



My PC tower is well out of the way under my main desk, theres not much I can do about it or power leads as theres only one socket in this room and I have to have everything ganged up through it.



It doesn’t affect my music but its damn annoying knowing that its there when mixing ITB is oh so quiet! Damn soundcards with no headphone socket!

Hi, This sounds like a ground loop. This happens when you have two bits of equipment that have a different value for their grounds, i.e. one has 0V and one is floating above 0V. What you hear is the current flowing to true ground along the interconnect to your amp and then to ground.

This happens a lot with laptops when they are plugged in, but not on batteries. It sound like this is due the the mixer, does it have a PSU like a laptop? You could try earthing the mixer, it should have each pins on the back.

Another common solution is to disconnect the ground on the offening unit, but don’t do that because it is dangerous.

Maplin sell ground loop isolators. The cheap ones just filter out the sound, so you don’t want to do that. You can get good ones that earth you interconnects.

RF inside a PC won’t make any difference unless you have faulty fans. They sell lots of high end audio cards and UAD DSPs that are PCI-e without any problems.

Maplin Ground Loop Isolator that claims to Totally preserves your audio signal:

http://www.maplin.co.uk/Module.aspx?ModuleNo=226569

Cheap filter version:

http://www.maplin.co.uk/Module.aspx?ModuleNo=33172

[quote]TheAnt (27/08/2010)[hr]It sound like this is due the the mixer, does it have a PSU like a laptop? You could try earthing the mixer, it should have each pins on the back.

[/quote]

Yeah, it has a PSU.  I didn’t notice any pin on the back of the mixer but I’ll certainly check later.  Strange how the mixer manual says nothing about grounding, you would think they would address it if their own supplied PSU can cause ground loops.

[quote]Strange how the mixer manual says nothing about grounding, you would think they would address it if their own supplied PSU can cause ground loops.[/quote]

It is more the combination of equipment used that causes a problem, the mixer, audio interface and amp. If the mixer wasn’t connected to your PC it might not have this problem.

I would go with the maplin or similar option if you don’t have access to an electrician :slight_smile: