Eliminating White Noise from audio input to PC

[PatrickHughesLive]

I'm try to set up a web stream in which I can broadcast video and audio of mixing live. I've managed to get everything on the video side of things worked out no problem but I can't get rid of some pretty severe white noise from the audio. The current set up is cdj 2k nexus into djm 900 nexus and then a rca to 3.5mm into the pc's mic in. I'm using xsplit broadcaster to stream however the audio has terrible white noise even outside of the program if I listen to it just straight through the system sounds.

From the mixer the sound is crystal clear and it plays great through monitor speakers as well as headphone cue so I'm thinking it's something on the pc's end possibly but I really don't know what exactly is causing the white noise just that it is very noticeable as soon as you hear the input on the pc. Anyone have any advice on how I could maybe change some settings on the pc or tweak the set up to clean up the audio.

[efinque]

The "white noise" you are referring to is most likely a result of poor grounding.. try another cable maybe?

[mitchiemasha]

Yes... check cable and consider buying a proper Audio Interface.

If not this might help.

When using the standard audio in on my PC, the audio in is set at 5 in the settings. As it's 0-100 5 is quite low. Setting the lowest setting possible* on the input allows for the highest signal to noise ratio. If yours is set at 100 the mixer will have to be very very low before the auto limiting for the converters kicks in and/or serious distortion. This very low input will not fare well against the noise in the electronics.

*I say this because on my PC, when I set it lower than 5, then boost the output of my mixer going into the PC, I can see the peaks of the audio cut off before it's hit 0. I use cool edit to see the recording, Sound Forge, Audacity, any record/wave editor will do. Finding the perfect level is simply trial and error.

A question. Are you using a Tower or a Laptop? If your using a laptop, unplugging it will reduce the noise or get a ground hum eliminator. Most newer laptops have fixed the serious noise issue. Manufactures didn't even realise it was an issue, for a long time, reading the trouble shooting they were providing back then in the early days was hilarious.

[PatrickHughesLive]

Currently using a cheap rca-3.5mm cable I got from best buy so shame on me for that I guess haha, just bought a nicer one off amazon so hopefully that will make a difference when it shows up in a couple days. I'm not familiar with what your referring to when you say proper audio interface, would that be some sort of stand alone device I would add between the mixer and laptop to clean up the sound?

[efinque]

Currently using a cheap rca-3.5mm cable I got from best buy so shame on me for that I guess haha, just bought a nicer one off amazon so hopefully that will make a difference when it shows up in a couple days. I'm not familiar with what your referring to when you say proper audio interface, would that be some sort of stand alone device I would add between the mixer and laptop to clean up the sound?

Yes they usually offer lower latency, better preamps and higher sample rate.

[PatrickHughesLive]

So I just solved my own problem by messing around so here's what worked for me. I used the usb out from the djm 900 nexus into a usb slot of the pc and installed the djm 900 software which gave me some flexibility on the input db and allowed me to treat it the same as any other audio line into the pc. And now I have absolutely no noise so this is what I'll go with for now. Thanks for the advice!

[Puregroove]

Mic is always a bit of a nasty input to use IMHO. I'm sure people have ways of making it sound good, but seems to me it just isn't designed for the job.

[mitchiemasha]

I was unaware the 900 could directly plug into a pc via usb... As it happens the audio interface I was referring to, your 900 nexus is already 1 of them.

This means you are eliminating the audio section on your mother board (most are crap) and the nexus is handling it for you.

[efinque]

I was unaware the 900 could directly plug into a pc via usb... As it happens the audio interface I was referring to, your 900 nexus is already 1 of them.

This means you are eliminating the audio section on your mother board (most are crap) and the nexus is handling it for you.

Some high-end PCI and PCI-E soundcards are good but it's true that the integrated ones are, well... crap.

[Puregroove]

Funnily enough, although recently I switched over to a USB interface with balanced leads and all that crap, for the past few years I'd been using just an old machine with an SBLive soundcard in it going in the line-in. Perfectly good results.