USB noise?

ilmeri · Post by **ilmeri** » Wed Jul 02, 2008 8:25 am

Hi!

I'm getting awful noise from my R3 when it's connected via USB. I mean it's not that awful, but still really noticeable. At the instant i unplug the USB cable, the noise disappears. Is this normal, can this be avoided? I remember having the same kind of problem with my good old Yamaha CS6X, even though it was attached with midi cables. I'm using a MBP with Apogee Duet.

slammah2012 · Post by **slammah2012** » Thu Jul 03, 2008 12:55 pm

ilmeri wrote:Hi!

I'm getting awful noise from my R3 when it's connected via USB. I mean it's not that awful, but still really noticeable. At the instant i unplug the USB cable, the noise disappears. Is this normal, can this be avoided? I remember having the same kind of problem with my good old Yamaha CS6X, even though it was attached with midi cables. I'm using a MBP with Apogee Duet.

were they attached to the same computer???

how good is your power source on your computer???...Grounding

rptr · Post by **rptr** » Mon Jul 07, 2008 5:54 am

Definitely a power issue... guitar amps are the same: they start to buzz with less power.

blinkofanI · Post by **blinkofanI** » Mon Jul 07, 2008 6:55 pm

Hi,
I'm willing to bet that your R3 audio outs are plugged in your Duet, isn't it? The problem you're encoutering is frequent. Your R3 is plugged in your AC outlet and so is your MBP. So, you're creating a ground loop. To verify, just unplug your MBP and let it run on its own. If the noise stops, you got a ground loop!! You can either make specials cables or buy a stereo DI box that will go between your R3 and Duet interface. You then switch on the ground lift switch and the noise will go away. If you respect your R3, don't buy a Tapco or Behringer DI!!! Good luck.

Blink

drsuds · Post by **drsuds** » Wed Jul 16, 2008 3:40 am

I have the same problem when connecting to my beheringer xenyx2424fx pa mixer. It's OK until I attempt to use with a distortion peddle. Then it's curtains for the ground noise. I've tried to rig up with a ground lift. But it's a no go. Thinking about a power conditioning unit to make my distortion rig work.

slammah2012 · Post by **slammah2012** » Wed Jul 16, 2008 4:17 am

drsuds wrote:I have the same problem when connecting to my beheringer xenyx2424fx pa mixer. It's OK until I attempt to use with a distortion peddle. Then it's curtains for the ground noise. I've tried to rig up with a ground lift. But it's a no go. Thinking about a power conditioning unit to make my distortion rig work.

That would be your distortion unit amplifying the voltage difference between your "house" ground and neutral....

try to use a cable with 100% shield.....if possible use a balanced cable with line transformers to cancel out any possible interferance...
Try to find a better ground (power source) than in the receptacle you are currently drawing from....

Watch out for noisy transformers......
FX Pedal AC adapters can create noise where batteries don't......

drsuds · Post by **drsuds** » Wed Jul 16, 2008 2:32 pm

slammah2012 wrote:
drsuds wrote:I have the same problem when connecting to my beheringer xenyx2424fx pa mixer. It's OK until I attempt to use with a distortion peddle. Then it's curtains for the ground noise. I've tried to rig up with a ground lift. But it's a no go. Thinking about a power conditioning unit to make my distortion rig work.
That would be your distortion unit amplifying the voltage difference between your "house" ground and neutral....

try to use a cable with 100% shield.....if possible use a balanced cable with line transformers to cancel out any possible interferance...
Try to find a better ground (power source) than in the receptacle you are currently drawing from....

Watch out for noisy transformers......
FX Pedal AC adapters can create noise where batteries don't......

I'm actually using a battery with it.

It's actually more complicated than that I think. I set up a send and return loop with the mixer... works ok UNTIL I plug in the R3, (where the noise originates from) It makes more noise than my computer that's hooked up to the same unit. and the noise is there with the computer off and disconnected.

Go figure.

slammah2012 · Post by **slammah2012** » Thu Jul 17, 2008 12:24 am

drsuds wrote:
slammah2012 wrote:
drsuds wrote:I have the same problem when connecting to my beheringer xenyx2424fx pa mixer. It's OK until I attempt to use with a distortion peddle. Then it's curtains for the ground noise. I've tried to rig up with a ground lift. But it's a no go. Thinking about a power conditioning unit to make my distortion rig work.
That would be your distortion unit amplifying the voltage difference between your "house" ground and neutral....

try to use a cable with 100% shield.....if possible use a balanced cable with line transformers to cancel out any possible interferance...
Try to find a better ground (power source) than in the receptacle you are currently drawing from....

Watch out for noisy transformers......
FX Pedal AC adapters can create noise where batteries don't......
I'm actually using a battery with it.

It's actually more complicated than that I think. I set up a send and return loop with the mixer... works ok UNTIL I plug in the R3, (where the noise originates from) It makes more noise than my computer that's hooked up to the same unit. and the noise is there with the computer off and disconnected.

Go figure.

Try a different channel.....it is an analog Behringer....
I have the Rackmount Behr 8 channel DI, and each channel has a different amount of hum usin the same settings and source.........the higher channels (7/8)are the cleanest...
also...
Let me guess....
You are running everything unbalanced (send and return)down the same cable teminated with a TRS (stereo 1/4")insert at the Behr end and a split to 2 mono jacks at the other..........if so, try lifting the shield at the input to your distortion....

The source of hum in audio is always from a voltage difference between ground and neutral....if there is ZERO resistance between your ground sources then you should be okay...If you are using a power bar with an indicator light on the main switch, or a fancy ground insulsator setup, you actually increase the chance of a weaker earth.....thus more noise....
If device "A" finds a better "ground" through a patch cable than through its AC connecter or a hardwired chasis to earth, you will have hum because that voltage difference gets amplified........

X-Trade · Post by **X-Trade** » Thu Jul 17, 2008 10:38 am

I used to get a problem on my behringer interface that came with my xenyx mixer. This was not ground noise as such because the device is USB bus powered, but I just unplugged the device from the motherboard USB and put it into my PCI card USB and it worked fine!
Basically i was getting lots of interferance from the power supply and processor clock. kind of a high pitched squaliing noise that would drop to a lower pitch whenever I moved the mouse or such.

I still get this problem but at a much lower level, but I can't easilly determine whether it is in my recordings or coming out of the sound card and not affecting it.

I also found that badly screened cables to my Korg TR was picking up interferance from the MIDI cables......

slammah2012 · Post by **slammah2012** » Thu Jul 17, 2008 1:00 pm

X-Trade wrote:I used to get a problem on my behringer interface that came with my xenyx mixer. This was not ground noise as such because the device is USB bus powered, but I just unplugged the device from the motherboard USB and put it into my PCI card USB and it worked fine!
Basically i was getting lots of interferance from the power supply and processor clock. kind of a high pitched squaliing noise that would drop to a lower pitch whenever I moved the mouse or such.

I still get this problem but at a much lower level, but I can't easilly determine whether it is in my recordings or coming out of the sound card and not affecting it.

I also found that badly screened cables to my Korg TR was picking up interferance from the MIDI cables......

That mouse thing is common......Optical mouses don't generate as much as ball mouses do....USB mouses can be adapted into the mouse din jack to further quiet things.... I find DVD and CD writters are famous for adding noise.....mute them in your windows mixer and see if it gets even quieter....

drsuds · Post by **drsuds** » Thu Jul 17, 2008 1:04 pm

slammah2012 wrote:
X-Trade wrote:I used to get a problem on my behringer interface that came with my xenyx mixer. This was not ground noise as such because the device is USB bus powered, but I just unplugged the device from the motherboard USB and put it into my PCI card USB and it worked fine!
Basically i was getting lots of interferance from the power supply and processor clock. kind of a high pitched squaliing noise that would drop to a lower pitch whenever I moved the mouse or such.

I still get this problem but at a much lower level, but I can't easilly determine whether it is in my recordings or coming out of the sound card and not affecting it.

I also found that badly screened cables to my Korg TR was picking up interferance from the MIDI cables......
That mouse thing is common......Optical mouses don't generate as much as ball mouses do....USB mouses can be adapted into the mouse din jack to further quiet things.... I find DVD and CD writters are famous for adding noise.....mute them in your windows mixer and see if it gets even quieter....

Yeah, agian on my end its really nutty. The r3 causes it. I've learned by trial and error. I don't really have much problem with noise seeping over from my pc. (I have in the past)

A good trick is to try and plug all your noise and main ground into one socket. that way there's no ground loop. I have had much less trouble since I bought all new, good quality cables for my setup.

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USB noise?

USB noise?

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